EEVblog Electronics Community Forum

Products => Test Equipment => Topic started by: EEVblog on October 13, 2020, 08:21:03 am

Title: New EEVblog BM786 Multimeter
Post by: EEVblog on October 13, 2020, 08:21:03 am
I'm now allowed to show it.
Stock coming end of this month.
The BM786 model will be exclusive to the EEVblog.
This is the US$150 class meter I've been talking about.
Supporters and those signed up to my newsletter will get first dibs.
Manual: https://www.eevblog.com/files/BM789-Manual-Original-Final.pdf (https://www.eevblog.com/files/BM789-Manual-Original-Final.pdf)
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 13, 2020, 08:23:25 am
PCB shots
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on October 13, 2020, 08:56:33 am
Final pricing available?
Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on October 13, 2020, 09:00:34 am
I quick look in the manual shows that 786 is nearly the same 785, except it adds temperature.
The 789 model has a couple of functions more and higher bandwidth on AC volt.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 13, 2020, 10:32:37 am
I quick look in the manual shows that 786 is nearly the same 785, except it adds temperature.
The 789 model has a couple of functions more and higher bandwidth on AC volt.

786 has nS + temp
Title: Re: New EEVblog BM786 Multimeter
Post by: coromonadalix on October 13, 2020, 10:50:53 am
Congrats, the manual is very explanatory    :-+

Will the firmware evolve from this point   IE  add functions, or now it will be maintenance and bugs correction

Is there a big price jump between the 3 models

the 786 is 150$    the other 2 ??
Title: Re: New EEVblog BM786 Multimeter
Post by: indeterminatus on October 13, 2020, 11:09:01 am
Nice :-DMM!
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 13, 2020, 11:43:45 am
Congrats, the manual is very explanatory    :-+
Will the firmware evolve from this point   IE  add functions, or now it will be maintenance and bugs correction

Just bug fixes if any, like the BM235 and all other Brymen meters.

Quote
Is there a big price jump between the 3 models
the 786 is 150$    the other 2 ??

I don't know the FOB prices for the others as they can't sell it to me due to existing dealer arrangements. So they created the BM786 just for me.
Brymen are very strict on these dealer agreements, it's the reason I can't sell the BM869 and others.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on October 14, 2020, 12:56:35 am
Congratulations on the release, Dave! That is a beautiful instrument that carries the pedigree of one of the greatest manufacturers these days.
Title: Re: New EEVblog BM786 Multimeter
Post by: BU508A on October 14, 2020, 01:17:42 am
Congratulations to the new meter, Dave.  :-+

Were you involved in the development process somehow? Defining specs? Asked by Brymen for a "wishlist"?  :D

Welectron (https://www.welectron.com/) in Germany is selling the BM235 EEVBlog edition DMM (https://www.welectron.com/Brymen-BM235-Multimeter-EEVBlog-Edition_1). Will the new BM786 also be distributed for Germany / the EU by Welectron?

Btw, I love blue multimeters on my bench.  :-+  :D
Title: Re: New EEVblog BM786 Multimeter
Post by: coromonadalix on October 14, 2020, 01:34:37 am
loll

I have the yellow ones, the red ones,  miss the blue and orange loll,  maybe some green tooo   :-DD
Title: Re: New EEVblog BM786 Multimeter
Post by: umbro on October 14, 2020, 02:18:46 am
Looks good :-DMM :-+
Title: Re: New EEVblog BM786 Multimeter
Post by: Bud on October 14, 2020, 02:36:13 am
Having both Brymen and EEVBlog branding is kind of silly, dont you guys think.  :-//
Title: Re: New EEVblog BM786 Multimeter
Post by: BU508A on October 14, 2020, 02:39:27 am
Having both Brymen and EEVBlog branding is kind of silly, dont you guys think.  :-//

/me is pointing Bud to the TEA thread...   :palm:  ::)   ;D
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on October 14, 2020, 03:14:38 am
Having both Brymen and EEVBlog branding is kind of silly, dont you guys think.  :-//
Not in the least.

Both brands have value - and both apply for this product.
Title: Re: New EEVblog BM786 Multimeter
Post by: Bud on October 14, 2020, 05:01:48 am
Your colleague asks you what multimeter you have. Your answer ?
Title: Re: New EEVblog BM786 Multimeter
Post by: Bud on October 14, 2020, 05:26:32 am
Having both Brymen and EEVBlog branding is kind of silly, dont you guys think.  :-//

/me is pointing Bud to the TEA thread...   :palm:  ::)   ;D

Thanks but no thanks. That topic has become a cloaca with arrival of some new people some time back.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 14, 2020, 06:55:30 am
Having both Brymen and EEVBlog branding is kind of silly, dont you guys think.  :-//

It's always been like that with the BM235.
I think there is some actual requirement for UL testing too, otherwise it has to get tested again for each brand.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 14, 2020, 06:58:41 am
Were you involved in the development process somehow? Defining specs? Asked by Brymen for a "wishlist"?  :D

Not the actual specs, they approached me with the new series in which they are obviously targeting the Fluke 70 series with the overmoulded design.
But I did get the nS feature added on the BM786 and have got them to make a few firmware changes and bugs fixed based on my testing.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 14, 2020, 06:59:27 am
Welectron (https://www.welectron.com/) in Germany is selling the BM235 EEVBlog edition DMM (https://www.welectron.com/Brymen-BM235-Multimeter-EEVBlog-Edition_1). Will the new BM786 also be distributed for Germany / the EU by Welectron?

If they ask for it, maybe.
This first batch is just for me though.
Title: Re: New EEVblog BM786 Multimeter
Post by: coromonadalix on October 14, 2020, 10:50:53 am
Having both Brymen and EEVBlog branding is kind of silly, dont you guys think.  :-//


I dont find this silly at all,  i would be proud of it, Dave helped Brymen for this model, i find this rewarding,   if some company or brands would listen feedback more often, i think some product could greatly evolve.
Title: Re: New EEVblog BM786 Multimeter
Post by: Mechatrommer on October 14, 2020, 11:04:04 am
Having both Brymen and EEVBlog branding is kind of silly, dont you guys think.  :-//
Brymen is the manufacturer, EEVBlog is publicity stunt much like artist.. if you see a shirt with <Marylin Monroe> <or insert your favourite artist> picture on it and Lee Cooper name on the neck tag, will you buy it because of what? the picture? or the neck tag? the manufacturer will get the money, some percentage to sellers and probably royalty to the artist stunt, but since Marylin is currently integrating with hydrocarbon pool, royalty will not do any good to her.
Title: Re: New EEVblog BM786 Multimeter
Post by: MiroS on October 14, 2020, 11:16:48 am
Having both Brymen and EEVBlog branding is kind of silly, dont you guys think.  :-//
Brymen is the manufacturer, EEVBlog is publicity stunt much like artist.. if you see a shirt with <Marylin Monroe> <or insert your favourite artist> picture on it and Lee Cooper name on the neck tag, will you buy it because of what? the picture? or the neck tag? the manufacturer will get the money, some percentage to sellers and probably royalty to the artist stunt, but since Marylin is currently integrating with hydrocarbon pool, royalty will not do any good to her.

I think important may be also  quick/trusted local support, low delivery cost/time and popularity. Unique product has usually unique quirks :) More folks will use it , less bugs will remain not solved.
Fortunately this is Brymen, but anyway I think they will first take care for their main product line than for niche product 'business is business'.

Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 14, 2020, 12:38:41 pm
I think important may be also  quick/trusted local support, low delivery cost/time and popularity. Unique product has usually unique quirks :) More folks will use it , less bugs will remain not solved.
Fortunately this is Brymen, but anyway I think they will first take care for their main product line than for niche product 'business is business'.

Eer, this is their "main product line". It's their brand new design that will be sold by every dealer around the world.
That they changed the colour to blue and changed a couple of lines of code for a version for me makes no difference. All issues/bug fixes found on the others models automatically get fixed on my model, and vice-versa.
Note the model options on the PCB in the photo above, near the connectors, they allowed for the possibility of models 783 through 789.
FYI, virtually all of the issues, both hardware and software found on the BM235, were found by EEVblog users, not by people buying the identical Brymen branded BM235.
Title: Re: New EEVblog BM786 Multimeter
Post by: tszaboo on October 14, 2020, 12:41:42 pm
Really nice. I have some questions:
Does it work well with rechargeable AAA batteries?
Does it come with a Cal certificate?

It looks to have very useful features for this price, I think I want to buy a few of them for work.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 14, 2020, 12:46:04 pm
Really nice. I have some questions:
Does it work well with rechargeable AAA batteries?
Does it come with a Cal certificate?

It should work ok with rehcargables:
https://www.eevblog.com/forum/testgear/us (https://www.eevblog.com/forum/testgear/us)$150-class-multimeter/msg3077681/#msg3077681
No cal certificate, just like other Brymens.
Title: Re: New EEVblog BM786 Multimeter
Post by: BravoV on October 14, 2020, 12:52:11 pm
Does it work well with rechargeable AAA batteries?

+1 , and also Lithium cells ? As these have tad higher voltage.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 14, 2020, 12:54:11 pm
BTW, I don't actually have the blue version yet, it's on the courier truck. I only have the red proto version.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 14, 2020, 12:54:33 pm
Does it work well with rechargeable AAA batteries?
+1 , and also Lithium cells ? As these have tad higher voltage.

Yes, confirmed ok by Brymen.
Title: Re: New EEVblog BM786 Multimeter
Post by: tszaboo on October 14, 2020, 01:02:45 pm
Really nice. I have some questions:
Does it work well with rechargeable AAA batteries?
Does it come with a Cal certificate?

It should work ok with rehcargables:
https://www.eevblog.com/forum/testgear/us (https://www.eevblog.com/forum/testgear/us)$150-class-multimeter/msg3077681/#msg3077681
No cal certificate, just like other Brymens.
Well, 3.55V/3= 1.18V. That is around 50% DoD of a NiMH, so not perfect.
I guess we buy a pack of alkaline then.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on October 14, 2020, 03:27:33 pm

A question?

Will firmware be field upgradeable?
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 15, 2020, 02:25:27 am
Will firmware be field upgradeable?

Technically there is a programming header inside, but Brymen are super secret about their processor used. So that's a "no" for now.
At least it's programable, unlike the BM235 which uses an OTP part.
Title: Re: New EEVblog BM786 Multimeter
Post by: Monkeh on October 15, 2020, 03:43:50 am
Will firmware be field upgradeable?

Technically there is a programming header inside, but Brymen are super secret about their processor used. So that's a "no" for now.
At least it's programable, unlike the BM235 which uses an OTP part.

I'd say send one off for a decapping and see what it is, but I wouldn't want to hurt a relationship for idle curiosity.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 15, 2020, 10:49:32 am
Will firmware be field upgradeable?

Technically there is a programming header inside, but Brymen are super secret about their processor used. So that's a "no" for now.
At least it's programable, unlike the BM235 which uses an OTP part.

I'd say send one off for a decapping and see what it is, but I wouldn't want to hurt a relationship for idle curiosity.

My guess is one of the really low end asian brands. On both the BM235 and this one they talk about struggles having enough memory to add new functions, so it's very memory limited.
Title: Re: New EEVblog BM786 Multimeter
Post by: Electro Fan on October 15, 2020, 07:48:14 pm
BM786 looks really good but any chance it actually weighs 635g?  Fluke 179 is similar in dimensions (although can't say for sure about the depth/thickness front to back as far as case/probe holder vs. meter itself), but the 179 is 420g.  Also, compare the weight and HWD in the 786 manual to the weight and HWD of the BM869S.  Maybe the 786 manual specs for weight (or otherwise maybe HWD) need an edit?  Just curious.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 15, 2020, 10:41:16 pm
BM786 looks really good but any chance it actually weighs 635g?  Fluke 179 is similar in dimensions (although can't say for sure about the depth/thickness front to back as far as case/probe holder vs. meter itself), but the 179 is 420g.  Also, compare the weight and HWD in the 786 manual to the weight and HWD of the BM869S.  Maybe the 786 manual specs for weight (or otherwise maybe HWD) need an edit?  Just curious.

Yeah, mistake. It's 414g with batteries. My 77-IV is 408g.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 15, 2020, 10:45:09 pm
vs the 77IV for those curious.
Title: Re: New EEVblog BM786 Multimeter
Post by: sdt on October 15, 2020, 11:05:03 pm
How do the DC+AC modes work?

Does it flip back and forth between separate DC & AC measurements?
Title: Re: New EEVblog BM786 Multimeter
Post by: Electro Fan on October 15, 2020, 11:30:49 pm
vs the 77IV for those curious.

Your new meter is going to be very popular.  Congrats!
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on October 16, 2020, 05:35:40 pm
How do the DC+AC modes work?

Does it flip back and forth between separate DC & AC measurements?
I don't know about this meter, but in my BM857 (also single display) the AC+DC adds the DC with the AC RMS value of the input, and you can cycle between AC, DC and AC+DC modes using the buttons.
Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on October 16, 2020, 06:24:38 pm
AC+DC is always a single value compromised of sqrt(sqr(AC)+sqr(DC)), the question is how the meter does this.
Most meters reads a AC value, then a DC value and then do the calculation, i.e. reducing the update rate, a few meters may be able to do a combine AC+DC measurement in one conversion. When doing separate AC and DC measurement there is also a issue about the time needed to do the switch between them.
Title: Re: New EEVblog BM786 Multimeter
Post by: MosherIV on October 16, 2020, 07:02:33 pm
I think te question about ac+dc is more about how is it displayed with only single display.

My Fluke 187 does it but has dual display.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on October 16, 2020, 07:55:22 pm
I think te question about ac+dc is more about how is it displayed with only single display.

My Fluke 187 does it but has dual display.
That is how I understood the question when I provided my reply above.
Title: Re: New EEVblog BM786 Multimeter
Post by: ogdento on October 16, 2020, 10:29:26 pm
This is nearly the only meter I'd ever need.  My only gripe is there's no low-z (on the 786)... will there be an eevblog-blue 789?
Title: Re: New EEVblog BM786 Multimeter
Post by: sdt on October 16, 2020, 11:45:36 pm
That is how I understood the question when I provided my reply above.

Thanks for the replies, that clears up a lot.

Neither of my two meters (ut139c & an8008) have any sort of combined AC & DC modes. I've seen meters with dual display, but not come across DC+AC before.

To be honest I'd never even considered what the AC mode would report in the presence of a DC offset. From the comments I take it the AC mode is AC coupled and ignores the DC offset, and the DC+AC mode is the numeric sum of what the DC and AC modes would report.
Title: Re: New EEVblog BM786 Multimeter
Post by: ve7xen on October 17, 2020, 12:14:10 am
To be honest I'd never even considered what the AC mode would report in the presence of a DC offset. From the comments I take it the AC mode is AC coupled and ignores the DC offset, and the DC+AC mode is the numeric sum of what the DC and AC modes would report.

Yes, though it is the geometric mean, not sum. It is giving you the total RMS value of the input, rather than the RMS value of the AC or DC components only (which is what you [ideally] get in those respective modes).

I think there are some DMMs out there that don't actually AC-couple the AC range, so YMMV, but this is what would normally be expected.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 17, 2020, 06:14:13 am
will there be an eevblog-blue 789?

No, I'm not allowed to sell it, as there is an official Australian dealer who has already said they want to carry it.
Good luck trying to buy it from them: https://www.cabac.com.au/ (https://www.cabac.com.au/)
I don't know why they bother with Cabac, I'd sell 100 times the meters they would.

Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 17, 2020, 06:17:44 am
AC+DC is always a single value compromised of sqrt(sqr(AC)+sqr(DC)), the question is how the meter does this.
Most meters reads a AC value, then a DC value and then do the calculation, i.e. reducing the update rate, a few meters may be able to do a combine AC+DC measurement in one conversion. When doing separate AC and DC measurement there is also a issue about the time needed to do the switch between them.

This is why the AC+DC mode is on the DC range switch. It can measure DC and then switch in an AC coupling cap, and then it display the  combined DC+AC value.
Title: Re: New EEVblog BM786 Multimeter
Post by: wolfy007 on October 17, 2020, 07:38:50 am
will there be an eevblog-blue 789?

No, I'm not allowed to sell it, as there is an official Australian dealer who has already said they want to carry it.
Good luck trying to buy it from them: https://www.cabac.com.au/ (https://www.cabac.com.au/)
I don't know why they bother with Cabac, I'd sell 100 times the meters they would.

I remember them, their online store is still shit I see, I remember I ended up buying a Brymen meter I wanted from Europe instead of them.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on October 17, 2020, 11:02:46 am
On my multimeter (UT71D), the voltage AC+DC is constantly converted to true RMS by the AD636.

Vrms= Avg x [Vin^2/Vrms]

If AC only is required, Vin is routed through a capacitor before reaching the true RMS converter.
The AC/AC+DC switch works on the V AC selector position only.
The DC component is read on the V DC selector position.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on October 17, 2020, 12:03:12 pm
On my multimeter (UT71D), the voltage AC+DC is always converted to true RMS by the AD636.

Vrms= Avg x [Vin^2/Vrms]

If AC only is required, Vin is routed through a capacitor before reaching the true RMS converter.
The AC/AC+DC switch works on the V AC selector position only.
The DC component is read on the V DC selector position.

You are correct, RMS converter by definition converts AC+DC value by definition (it just a waveform to them). So if you DC couple them you get AC+DC, if you AC couple them you get AC RMS only.

People are probably confused by DUAL display mode on (for instance BM869S) that shows AC RMS and AC+DC RMS od screen at the same time... Those two are separate measurements that need to be switched back and forth between modes.

Title: Re: New EEVblog BM786 Multimeter
Post by: ogdento on October 17, 2020, 11:50:51 pm
Too bad about the 789, but I guess it really doesn't matter... the 786 is fantastic for my electronics tinkering and would probably never leave my bench anyway. (Not that it couldn't handle it, but there's no reason to drag it under the house or into the attic).  The old bm257 has low-z/ef and can sit in the tool bag for the household wiring jobs.
Title: Re: New EEVblog BM786 Multimeter
Post by: multiJ on October 22, 2020, 12:12:42 pm
joeqsmith has in hand the new Brymen 7series multimeter(s?) for testing  :)

at 9.04
https://www.youtube.com/watch?v=bDIx4ik0vvA&feature=emb_logo (https://www.youtube.com/watch?v=bDIx4ik0vvA&feature=emb_logo)
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 22, 2020, 06:43:50 pm
joeqsmith has in hand the new Brymen 7series multimeter(s?) for testing  :)
...

The one I pulled out is the BM786.  As I mentioned, Brymen does not yet have the generic front covers for it.  Rather than wait, the meter was shipped with a different cover, similar to what Dave has shown.   The PCB, firmware and back case half are all the release versions so as far as making a review we should be good.   I was very clear of my intent and Brymen was onboard. 

Brymen has stood behind their products from day one.  Like me, I think they like seeing how their designs stack up against other brands on a level playing field.   I'm looking forward to seeing how it holds up.   
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 22, 2020, 09:42:26 pm
joeqsmith has in hand the new Brymen 7series multimeter(s?) for testing  :)
...
The one I pulled out is the BM786.  As I mentioned, Brymen does not yet have the generic front covers for it.  Rather than wait, the meter was shipped with a different cover, similar to what Dave has shown.   The PCB, firmware and back case half are all the release versions so as far as making a review we should be good.

I just got the final blue branded version, was going to do an unboxing video, but here you go. Note the decal stickers on the red proto.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 23, 2020, 02:07:04 am
I'm not too concerned with them using stickers to change the lettering on this meter.  The only time it would be a problem is during my chemical tests.   I will just avoid those areas. 
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 23, 2020, 03:16:46 am
I'm not too concerned with them using stickers to change the lettering on this meter.  The only time it would be a problem is during my chemical tests.   I will just avoid those areas.

I'm not sure a non-sticker red version exists, they went straight to blue for me.
So likely the one you got is one of a bunch they built to have sent to UL for testing. Should be identical to the shipped blue version but I haven't opened mine yet to confirm. My internal photos above are from my red sticker version.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 23, 2020, 12:48:55 pm
I'm not too concerned with them using stickers to change the lettering on this meter.  The only time it would be a problem is during my chemical tests.   I will just avoid those areas.

I'm not sure a non-sticker red version exists, they went straight to blue for me.
So likely the one you got is one of a bunch they built to have sent to UL for testing. Should be identical to the shipped blue version but I haven't opened mine yet to confirm. My internal photos above are from my red sticker version.

From above:
Quote
As I mentioned, Brymen does not yet have the generic front covers for it.  Rather than wait, the meter was shipped with a different cover, similar to what Dave has shown.   The PCB, firmware and back case half are all the release versions so as far as making a review we should be good.

I could have waited for the final cover but Brymen was fine with me showing it with the taped cover.  I plan to start working on it over the weekend.  Being a Brymen, I am not anticipating anything but a boring review where the meter just works... :-DD   
Title: Re: New EEVblog BM786 Multimeter
Post by: radiolistener on October 23, 2020, 01:25:34 pm
The first thing that catches my eye is that this new DMM has 60000 count instead of 500000 count like BM-867/869.

What is the reason to use less than 500000 count chipset for modern DMM?
Title: Re: New EEVblog BM786 Multimeter
Post by: multiJ on October 23, 2020, 01:30:56 pm
The first thing that catches my eye is that this new DMM has 60000 count instead of 500000 count like BM-867/869.

What is the reason to use less than 500000 count chipset for modern DMM?

Cost?
Title: Re: New EEVblog BM786 Multimeter
Post by: radiolistener on October 23, 2020, 01:44:59 pm
Cost?

I bought BM867 for about 150 USD.
This BM786 price is also 150 USD.


But BM867 has 500000 count mode, while BM786 has just 60000 count.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on October 23, 2020, 02:15:26 pm
500,000 count is just for higher resolution on DC volt. It does not improve your accuracy.
Some may find it useful to watch a battery draining slowly, for instance.
Not a deal breaker for most users.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on October 23, 2020, 02:25:59 pm
Cost?

I bought BM867 for about 150 USD.
This BM786 price is also 150 USD.


But BM867 has 500000 count mode, while BM786 has just 60000 count.

To me bigger difference is dual display vs single display. It is more of a refreshed addition to of 857/9 series..
Title: Re: New EEVblog BM786 Multimeter
Post by: coromonadalix on October 23, 2020, 02:28:43 pm
I always hate how people see "that 500k  count mode",  its an real 50k count      with an added bonus ...   

I love the 60k count of the 786,  maybe a 600k count hack with another lcd      loll

We love huge display counts  loll


Great job for the 786  Dave



Title: Re: New EEVblog BM786 Multimeter
Post by: Electro Fan on October 23, 2020, 02:35:32 pm
786 is a friendlier size and weight than the 867.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 23, 2020, 03:16:34 pm
I also use the BM869s high resolution mode.  It's too bad it's not supported in all modes.    That Gossen Ultra or what ever they call it now is a 300,000 count meter for about $850.   Normally I am using the old bench meters.    I'm also a fan of dual and tri-display meters, assuming they actually display something useful. 

***
Actually, what I should have wrote about the 500K mode is it would have been nice to have a sticky mode where it is always active.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 23, 2020, 09:15:26 pm
Cost?
I bought BM867 for about 150 USD.
This BM786 price is also 150 USD.
But BM867 has 500000 count mode, while BM786 has just 60000 count.

$150 is not the normal price for the BM867
The BM786 is smaller and has features not found on the BM867.
I can assure you the FOB cost of the BM786 is lower.
Having the extra digit requires more segments on the LCD, and possibly a bigger or extra driver chip as a result, and a bigger case or smaller font.
500,000 count is no use for what appears to be the intended market of a Fluke 70 series competitor.
There might also be other compromises.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 23, 2020, 09:18:37 pm
I always hate how people see "that 500k  count mode",  its an real 50k count      with an added bonus ...   
I love the 60k count of the 786,  maybe a 600k count hack with another lcd      loll

Remember, 20% of the time the 60,000 count BM786 is going to have the same resolution as the 500,000 count BM876, and at better accuracy.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on October 24, 2020, 11:09:35 am
Cost?
I bought BM867 for about 150 USD.
This BM786 price is also 150 USD.
But BM867 has 500000 count mode, while BM786 has just 60000 count.

$150 is not the normal price for the BM867
I have been following the prices of this model for a few years and the price at the tme site has been stuck at US$156.00.
https://www.tme.com/us/en-us/details/bm867/portable-digital-multimeters/brymen/bm867s/ (https://www.tme.com/us/en-us/details/bm867/portable-digital-multimeters/brymen/bm867s/)

500,000 count is no use for what appears to be the intended market of a Fluke 70 series competitor.
The 500k count is just a trend viewer - useful for charges and discharges, but with very loose accuracy. Something similar to the 20k count mode of the 87V.

What I really want to see is if the BM786 in 60k count is snappier than Keysight's U1282A.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on October 24, 2020, 11:55:16 am
What I really want to see is if the BM786 in 60k count is snappier than Keysight's U1282A.

Check out Joe's video:

https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg3293014/#msg3293014 (https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg3293014/#msg3293014)
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 24, 2020, 04:23:43 pm
The 500k count is just a trend viewer - useful for charges and discharges, but with very loose accuracy. Something similar to the 20k count mode of the 87V.

What I really want to see is if the BM786 in 60k count is snappier than Keysight's U1282A.
I tend to agree.  It's common that I am more interested in relative numbers than absolute.  How much something drifts for example.   It's proven to be useful. 
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on October 24, 2020, 10:21:59 pm
The 500k count is just a trend viewer - useful for charges and discharges, but with very loose accuracy. Something similar to the 20k count mode of the 87V.

What I really want to see is if the BM786 in 60k count is snappier than Keysight's U1282A.
I tend to agree.  It's common that I am more interested in relative numbers than absolute.  How much something drifts for example.   It's proven to be useful.
Yes, for that the 500k count mode is great.

BTW, congratulations on getting the new Brymen as an exclusive. I'll watch the video later.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 24, 2020, 11:43:31 pm
What I really want to see is if the BM786 in 60k count is snappier than Keysight's U1282A.

It'll do 10 times/sec updating in capture mode, so fast it's a bit disconcerting.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on October 25, 2020, 10:49:19 am
What I really want to see is if the BM786 in 60k count is snappier than Keysight's U1282A.

It'll do 10 times/sec updating in capture mode, so fast it's a bit disconcerting.
Thank you. I meant the settling rate of the autorange but that is quite a good rate as well. 

After watching Joe's video, I could tell the two seem to use different approaches for the autorange. I did a side-by-side comparison timing with the ohms and capacitance ranges (the ones where the lag is larger). Joe mentioned 15s to settle on the 40M measurement, while my Keysight was about 2s. This was becoming less dramatic as resistance decreased, with a crossing point of performance somewhere (didin't verify) and  the Keysight becomes slower to the point of taking almost 6s to read my 33 ohms resistor, while the Brymen becomes significantly faster.

Conductivity tests were similar in speed (perhaps because there are not many ranges to cycle).

I also saw an edge for the Keysight on the capacitance - not very dramatic, but both seem to pale in comparison to others such as the 87V, the UT61E or the U1273A. Voltages and current seemed quite equivalent.

I took these timings from Joe's video, thus this is not a definitive conclusion to the autorange performance at all.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 25, 2020, 01:52:30 pm
That's correct.  It's very slow in resistance with values over 10M, on the order of 10-15 seconds to settle with the 40M.  From the video, you can also see the 150pF took a fair bit of time but then so did the 100uF.   Part 2 will include a few more speed comparisons.       
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on October 25, 2020, 02:01:36 pm
That's correct.  It's very slow in resistance with values over 10M, on the order of 10-15 seconds to settle with the 40M.  From the video, you can also see the 150pF took a fair bit of time but then so did the 100uF.   Part 2 will include a few more speed comparisons.     
Ah, I got confused there. The 150pF on the Keysight was instantaneous (as with everything below 1uF) but the 100uF was about the same between the two.

BTW, I measured mine with a 100M resistor
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 25, 2020, 03:08:14 pm
The manual shows the high end for this meter is 60M.  They show a 0.1uA current for the 6M range and 0.01uA for the 60M range. 

If you wanted some closer numbers to compare it with yours, just let me know the value and we can set it up with the counter and high speed camera. 
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on October 28, 2020, 01:44:44 am
The manual shows the high end for this meter is 60M.  They show a 0.1uA current for the 6M range and 0.01uA for the 60M range. 

If you wanted some closer numbers to compare it with yours, just let me know the value and we can set it up with the counter and high speed camera.
Ah, no worries. I think the ballpark is accurate enough to expose how the two multimeters somewhat compare with each other in the capacitance and the ohms.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 28, 2020, 01:54:59 am
No problem.  It may be a while so if you come up with something later, I'm fine with it. 
Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on October 28, 2020, 02:17:30 pm
The first thing that catches my eye is that this new DMM has 60000 count instead of 500000 count like BM-867/869.

What is the reason to use less than 500000 count chipset for modern DMM?

The first thing that comes up when I see comments like this is how accurate are those 500,000 count hand held DMM's?   

The second thing that comes to mind is how often do you really need to resolve to that many digits in a handheld.    If I'm about to calibrate something I will use a device (handheld or not) that is designed for the task at hand.   More importantly that device will be on some sort of calibration schedule.    Most DMM's of the handheld variety are seldom kept on a stringent cal program.   That is the case in the hobby world as well as the commercial world.   

60,000 counts in a handheld device is a bit of a luxury as in many use cases you can get buy with 3-4 digits easy.   In fact sometimes you are better off with fewer digits.    Sometimes too much info is a bad thing.   By the way I'm not trying to say that high precision and high resolution is a bad thing in a handheld meter, just that for many users it really serves no purpose.

For example at work I'm involved in industrial systems under 600 VAC and similar for DC systems.   I can't ever remember needing to know the voltages on such systems beyond the first decimal point.   At lower control system voltages under 24 VDC you seldom need to know what power supplies are doing beyond the second decimal point.   It is only when you get involved in instrumentation that accuracy and resolution are important for calibration work, at that point you are working with traceable instruments anyways.   So 60,000 counts is more than good enough in this context.
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on October 28, 2020, 02:26:45 pm
As has been mentioned before, accuracy to 5 or 6 digits is rarely needed on most people's bench - but 5 or 6 digits of resolution are often very useful.

For example - If I have a reading of 4.5678V and when I alter the circuit somehow, the reading becomes 4.5675, then I have a pretty good idea the voltage went down - just a little.  Sometimes, that's exactly the bit of information you need.  The absolute accuracy could be out by 10%, but the change will still be a valid observation.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on October 28, 2020, 06:20:38 pm
The first thing that catches my eye is that this new DMM has 60000 count instead of 500000 count like BM-867/869.

What is the reason to use less than 500000 count chipset for modern DMM?

Simple: Because even 6000 counts is 0.016% accuracy. Supporting 6000 counts properly already requires very high precision components.

Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on October 28, 2020, 06:27:16 pm
Simple: Because even 6000 counts is 0.016% accuracy. Supporting 6000 counts properly already requires very high precision components.

Usually not, it can be as bad as 0.16%
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on October 28, 2020, 07:25:56 pm
Simple: Because even 6000 counts is 0.016% accuracy. Supporting 6000 counts properly already requires very high precision components.

Usually not, it can be as bad as 0.16%

Sure, it drops down to 600 counts if you're measuring (eg.) 7V, that's 0.16%.

The solution isn't to go to 500k counts though. 10k counts would be 0.01% on all ranges.

If we apply Benford's law the ideal number of counts is 20k.

https://en.wikipedia.org/wiki/Benford%27s_law
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on October 28, 2020, 08:15:42 pm
Simple: Because even 6000 counts is 0.016% accuracy. Supporting 6000 counts properly already requires very high precision components.

Usually not, it can be as bad as 0.16%

Sure, it drops down to 600 counts if you're measuring (eg.) 7V, that's 0.16%.

The solution isn't to go to 500k counts though. 10k counts would be 0.01% on all ranges.

If we apply Benford's law the ideal number of counts is 20k.

https://en.wikipedia.org/wiki/Benford%27s_law

Benford's law is not so much relevant in electronics in this context. We have common voltages used: 5, 12, 13.2, 24, 48, 120, 240, 440 etc...
You measure according to system voltages, and those will have standardized, artificial grouping.

20000 is very good but 50000/60000 count is even better and keeps electronics measurements in long scale most of the time.

That is my observation.. Not a law.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 29, 2020, 12:09:26 am
If I only would have only taken a minute to read the title of that wiki page on Benford's law and became an expert, I could have saved myself $12K on the new 8.5 digit Keysight meter.   

Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 29, 2020, 02:40:57 am
For those interested in accuracy, the BM786 beats the BM869 on DC current, 0.075%+20  across three lowest ranges vs 0.1-0.15%.
And better on the high end at 0.3% vs 0.5%
Not bad considering the lower price point.
Title: Re: New EEVblog BM786 Multimeter
Post by: okurka on October 30, 2020, 06:28:43 am
The BM786 model will be exclusive to the EEVblog.

So Brymen won't sell the BM786 elsewhere with red housing, like they do with the BM235?
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on October 30, 2020, 06:58:09 am
So Brymen won't sell the BM786 elsewhere with red housing, like they do with the BM235?

The BM235 existed before Dave ordered a blue one.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 30, 2020, 07:39:42 am
So Brymen won't sell the BM786 elsewhere with red housing, like they do with the BM235?
The BM235 existed before Dave ordered a blue one.

Technically, but I was the first to sell it, and I helped a little in the development and debug. I knew about it more than a year before it came out. I was also appointed the sole Australian distributor.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 30, 2020, 07:41:49 am
The BM786 model will be exclusive to the EEVblog.
So Brymen won't sell the BM786 elsewhere with red housing, like they do with the BM235?

Correct, it's a mid range model just for me, because the "official" Brymen Australian dealer already called dibs on the BM789, and Brymen are fiercely loyal to their dealerships, even if those dealership are
hopeless. This is why I can't sell any other Brymen models.
Title: Re: New EEVblog BM786 Multimeter
Post by: Nixfried on October 30, 2020, 07:48:54 am
If I only would have only taken a minute to read the title of that wiki page on Benford's law and became an expert, I could have saved myself $12K on the new 8.5 digit Keysight meter.

Awesome! 3458a robustness test incoming?  >:D
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on October 30, 2020, 08:38:39 am
20000 is very good but 50000/60000 count is even better and keeps electronics measurements in long scale most of the time.

Why only "most of the time"? Shouldn't it be "all the time"?  :popcorn:

Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on October 30, 2020, 08:41:52 am
If I only would have only taken a minute to read the title of that wiki page on Benford's law and became an expert, I could have saved myself $12K on the new 8.5 digit Keysight meter.

Benford's law applies to any number of digits. All you need is a multimeter with a little oven in it.

(How many digits before we have to control air pressure, too? Anybody know? I'm sure I read somewhere that some multimeters have a maximum altitude in their specification.)
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on October 30, 2020, 09:04:20 am
20000 is very good but 50000/60000 count is even better and keeps electronics measurements in long scale most of the time.

Why only "most of the time"? Shouldn't it be "all the time"?  :popcorn:

Try measuring 7.0000V and see what happens.
Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on October 30, 2020, 09:19:47 am
(How many digits before we have to control air pressure, too? Anybody know? I'm sure I read somewhere that some multimeters have a maximum altitude in their specification.)

That is due to high voltage arching, more isolation distance is required at low pressure.
Title: Re: New EEVblog BM786 Multimeter
Post by: Kleinstein on October 30, 2020, 10:50:56 am
Another problem at high altitude is that cooling gets less effective, both passive and with a fan. At least the fan could compensate with a little more speed.
The main limit is the required (by the standards) distances going up at 2000 m altitude. So it's very common to find a break / limit at 2000 m, especially for higher voltage instruments.

There is a small effect of pressure detectable for the metal can references (e.g. LTZ1000, LTFLU) - something in the sub ppm range. So only relevant of the very high end. This would not really limit the use at higher altitude - maybe a point to those who send a reference to NIST in colorado.

There is always the problem of having voltage so you just have to switch to the next larger range. This can happen with 2000 counts and can happen with 6000 counts. There is nothing so special with the leading 1, it's more or less an even distribution on a log scale. It was a bit special in the old times (e.g nixi tubes) with the display part was expensive.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on October 30, 2020, 01:16:36 pm
The Fluke 87V manual says:

(https://www.eevblog.com/forum/testgear/new-eevblog-bm786-multimeter/?action=dlattach;attach=1100278;image)
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on October 30, 2020, 11:31:58 pm
If I only would have only taken a minute to read the title of that wiki page on Benford's law and became an expert, I could have saved myself $12K on the new 8.5 digit Keysight meter.

Awesome! 3458a robustness test incoming?  >:D

Once I learned I didn't need anything that fancy, I traded it in on a new Harbor Freight meter.
Title: Re: New EEVblog BM786 Multimeter
Post by: UnexpectedBill on October 31, 2020, 06:22:54 pm
I am curious if this meter will have any PC link/datalogging capabilities. Based on the manual and PCB pictures, I'm guessing that it will not.
Title: Re: New EEVblog BM786 Multimeter
Post by: coromonadalix on November 01, 2020, 03:41:56 am
nope  Dave said it wont have this option

if i recall something wasn't working properly ??
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 01, 2020, 08:54:14 am
I am curious if this meter will have any PC link/datalogging capabilities. Based on the manual and PCB pictures, I'm guessing that it will not.

It was supposed to have a Bluetooth model option, but there is now no ETA on that. It has an internal connector for it, but the proto I had did not have any activity on the pins. Haven't checked the final model yet.
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on November 01, 2020, 10:02:57 am
I am curious if this meter will have any PC link/datalogging capabilities. Based on the manual and PCB pictures, I'm guessing that it will not.

It was supposed to have a Bluetooth model option, but there is now no ETA on that. It has an internal connector for it, but the proto I had did not have any activity on the pins. Haven't checked the final model yet.

If it does end up with a BT module, it would be nice if it is not the low power version.

Battery life is not really an issue these days, given things are usually designed to run on NiMH cells, and the low power BT on the 121GW has proved to be troublesome in some circumstances, judging by the discussion thread.

I already have a few logging meters, but it never hurts to have another...
Title: Re: New EEVblog BM786 Multimeter
Post by: matthijs on November 01, 2020, 10:17:42 am
Can we expect it to be available in Europe? Looking for a new multimeter, but buying it from outside Europe is going to cost alot on customs.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 01, 2020, 10:27:26 am
Can we expect it to be available in Europe? Looking for a new multimeter, but buying it from outside Europe is going to cost alot on customs.

Sparky Labs and Welectron will carry it.
Title: Re: New EEVblog BM786 Multimeter
Post by: matthijs on November 01, 2020, 10:36:27 am
Perfect, can't wait to get one. Cheers.
Title: Re: New EEVblog BM786 Multimeter
Post by: Roger Need on November 02, 2020, 03:13:39 am
How can we buy the BM786 in Canada?  Will it be on amazon.ca?

Roger
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 02, 2020, 03:47:19 am
How can we buy the BM786 in Canada?  Will it be on amazon.ca?

Eventually, yes. Will be on my website first though, still waiting for ETA. End of October promised has come and gone.
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on November 02, 2020, 07:14:27 am
Have you emailed them about the bill for your first order yet?
Title: Re: New EEVblog BM786 Multimeter
Post by: Trader on November 02, 2020, 09:54:04 am
What's the Brymen top high-end DMM now?  BM869s (2011) or BM789 (2020)?
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on November 02, 2020, 10:09:34 am
What's the Brymen top high-end DMM now?  BM869s (2011) or BM789 (2020)?

What do you mean? For electrician that works on 3 phase systems, one with measurements for that would be top.

If you mean best DC specs and longest scale, than BM869S and BM859S are best still...
You must study datasheets closely, for some ranges BM859S is slightly better than BM869S...

Also, ask yourself how old is Fluke 87 or 287....
BM869S is a few years old version of BM869 (without S)...

It's a multimeter, nothing new there, electrons didn't change lately...

Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on November 02, 2020, 10:33:35 am
What's the Brymen top high-end DMM now?  BM869s (2011) or BM789 (2020)?

The BM869s.

500,000 counts in a dual display, CAT IV 1000V meter. What more could you ask for in a handheld?

PS: The 's' version indicates an upgrade over the original.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 02, 2020, 10:45:17 am
What's the Brymen top high-end DMM now?  BM869s (2011) or BM789 (2020)?

The BM869S
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 02, 2020, 10:50:11 am
The BM869s.
500,000 counts in a dual display, CAT IV 1000V meter. What more could you ask for in a handheld?

Depends on your needs. Basic stuff like AutoHold maybe? BeepLit continuity? EF tester? All standard on the new BM780 series.
Smaller and lighter perhaps?
For almost all people, the difference between CAT IV 1000V and CAT IV 600V spec is negligible.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 02, 2020, 10:51:31 am
What's the Brymen top high-end DMM now?  BM869s (2011) or BM789 (2020)?

What do you mean? For electrician that works on 3 phase systems, one with measurements for that would be top.

If you mean best DC specs and longest scale, than BM869S and BM859S are best still...

The lower cost BM786 beats the BM869 on Dc current spec BTW.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on November 02, 2020, 11:56:31 am
What more could you ask for in a handheld?
Smaller and lighter perhaps?

OK, that...  :)
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 03, 2020, 02:00:53 am
Quote
We found few unpredictable problems during BM786 first production lot. Our RDs & production are working on solving them and should be able to fix them shortly. I hope BM786 would be able to be ready for shipment by Nov 15. Will keep you updated.
Title: Re: New EEVblog BM786 Multimeter
Post by: Chalton_trc on November 12, 2020, 03:33:40 pm
I like options like AutoHold, BeepLit continuity, V LoZ, V higher diode. Although I can live without them. I am more concerned about its reliability and that its problems are solved. This model had problems with auto-range, had problems with voltage when raising the frequency and also when measuring voltage in square wave when its frequency was varied. I don't know if all this has been solved today.
Title: Re: New EEVblog BM786 Multimeter
Post by: MiroS on November 12, 2020, 06:23:10 pm
https://www.welectron.com/Brymen-BM789-Multimeter (https://www.welectron.com/Brymen-BM789-Multimeter)
https://www.welectron.com/Brymen-BM786-Multimeter-EEVBlog-Edition (https://www.welectron.com/Brymen-BM786-Multimeter-EEVBlog-Edition)
https://www.welectron.com/Brymen-BM785-Multimeter (https://www.welectron.com/Brymen-BM785-Multimeter)
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 13, 2020, 02:51:22 am
Update: The Nov 15th shipping date has slipped with no new ETA, they are still working on issues.
Title: Re: New EEVblog BM786 Multimeter
Post by: Andrew McNamara on November 13, 2020, 03:06:09 am
Update: The Nov 15th shipping date has slipped with no new ETA, they are still working on issues.

Given their meters are typically not field updatable, this is A Good Thing.  :-+
Title: Re: New EEVblog BM786 Multimeter
Post by: Chalton_trc on November 13, 2020, 11:30:10 am
Has youth problems. But when it matures and they fix their problems ... if they get the reliability of a BM869, the 7-series will be a great meter.
Title: Re: New EEVblog BM786 Multimeter
Post by: MiroS on November 13, 2020, 12:17:53 pm
Has youth problems. But when it matures and they fix their problems ... if they get the reliability of a BM869, the 7-series will be a great meter.

I would wait year at least , if no desperate need.
Title: Re: New EEVblog BM786 Multimeter
Post by: Monkeh on November 13, 2020, 04:15:17 pm
https://www.welectron.com/Brymen-BM789-Multimeter (https://www.welectron.com/Brymen-BM789-Multimeter)
https://www.welectron.com/Brymen-BM786-Multimeter-EEVBlog-Edition (https://www.welectron.com/Brymen-BM786-Multimeter-EEVBlog-Edition)
https://www.welectron.com/Brymen-BM785-Multimeter (https://www.welectron.com/Brymen-BM785-Multimeter)

At those prices, no offence to Dave, I'd be sticking with a red one.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 16, 2020, 07:43:33 am
https://www.welectron.com/Brymen-BM789-Multimeter (https://www.welectron.com/Brymen-BM789-Multimeter)
https://www.welectron.com/Brymen-BM786-Multimeter-EEVBlog-Edition (https://www.welectron.com/Brymen-BM786-Multimeter-EEVBlog-Edition)
https://www.welectron.com/Brymen-BM785-Multimeter (https://www.welectron.com/Brymen-BM785-Multimeter)
At those prices, no offence to Dave, I'd be sticking with a red one.

I have no control over what Welectron sell it for.
To be fair, my commission from them on the BM786 would likely be worth more than the FOB price difference between the BM789 on which they would pay no commission.
I can sell it for well under US$150 direct on my store. It will be US$175 on Amazon.
Sparky Labs might be able to sell it cheaper than Welectron for those in the EU, but we'll see.
Title: Re: New EEVblog BM786 Multimeter
Post by: Specmaster on November 16, 2020, 10:20:14 am
What's the Brymen top high-end DMM now?  BM869s (2011) or BM789 (2020)?

What do you mean? For electrician that works on 3 phase systems, one with measurements for that would be top.

If you mean best DC specs and longest scale, than BM869S and BM859S are best still...

The lower cost BM786 beats the BM869 on Dc current spec BTW.

If you don't need the temperature scale, how about the 867S?
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on November 16, 2020, 10:54:51 am
What's the Brymen top high-end DMM now?  BM869s (2011) or BM789 (2020)?

What do you mean? For electrician that works on 3 phase systems, one with measurements for that would be top.

If you mean best DC specs and longest scale, than BM869S and BM859S are best still...

The lower cost BM786 beats the BM869 on Dc current spec BTW.

If you don't need the temperature scale, how about the 867S?

BM867 has only advantage of dual display screen.

Correct comparison is with older single display 857/859 that have comparable accuracy. BM785/6/9 are more of a refresh of those single display meters. Honestly, 60000 display is good enough (500000 mode is of limited use) and BM78x series have nice features (remembers sound preferences, backlight was improved, has AutoHold, has Diode test mode same as Flukes, flashes light on continuity etc, check datasheet for details) that are supposed to remove some of complaints of traditional Fluke users.

Basicaly, Brymen BM789 series makes Fluke 87V seriously not worth the money they ask for it...
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 16, 2020, 10:53:33 pm
Basicaly, Brymen BM789 series makes Fluke 87V seriously not worth the money they ask for it...

The BM780 series has the same overmolded rubber housing, size and shape as the Fluke 70 series, so it's clearly designed to compete with that. But it also has the electronics capability of the 87V as well.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 16, 2020, 10:56:22 pm
What's the Brymen top high-end DMM now?  BM869s (2011) or BM789 (2020)?
What do you mean? For electrician that works on 3 phase systems, one with measurements for that would be top.
If you mean best DC specs and longest scale, than BM869S and BM859S are best still...
The lower cost BM786 beats the BM869 on Dc current spec BTW.
If you don't need the temperature scale, how about the 867S?

The BM867S still misses out on AutoHold, EF tester, Beeplit continuity, and is bigger and heavier.
Title: Re: New EEVblog BM786 Multimeter
Post by: Specmaster on November 17, 2020, 01:50:37 pm
Not quite true, if you press the REC button on the 867s before taking a measurement, then apply the probes to the DUT, or voltage source, then the meter does indeed record the HIGH value for you, not sure if this a documented feature or not, but it is handy.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on November 17, 2020, 02:04:47 pm
Specmaster, by HIGH you mean the highest value read? The Autohold continuously monitors the inputs and holds (and beeps) for any stable measurement, regardless of any previous value.

The BM78x family having autohold is indeed a great advantage over the BM85x/BM86x, but the price differences and the feature overlaps surely don't help when trying to make a decision.
Title: Re: New EEVblog BM786 Multimeter
Post by: Specmaster on November 17, 2020, 02:33:24 pm
Correct, it is the highest value and you measure another voltage which is higher, then the meter will beep and store that new value, but has to be higher than the last one.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on November 17, 2020, 03:20:35 pm
It is documented. REC gives you the usual Max/Min/Average values as on other multimeters.
Title: Re: New EEVblog BM786 Multimeter
Post by: maginnovision on November 17, 2020, 05:29:23 pm
Yea, that's an entirely different thing.
Title: Re: New EEVblog BM786 Multimeter
Post by: Specmaster on November 17, 2020, 05:56:28 pm
It is documented. REC gives you the usual Max/Min/Average values as on other multimeters.
Yes I understand that, but what I'm saying here is, that the REC is a possible workaround to the issue of autohold, unless autohold will automatically reset itself each time, then you will have to manually reset it, then surely the REC function works in just same fashion, except, if you then probe another point of the DUT, if that voltage is higher than it will overwrite the held value.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 17, 2020, 10:25:39 pm
It is documented. REC gives you the usual Max/Min/Average values as on other multimeters.
Yes I understand that, but what I'm saying here is, that the REC is a possible workaround to the issue of autohold, unless autohold will automatically reset itself each time

AutoHold does reset itself, that's why it's called AUTOhold. Just like the original Fluke TouchHold who I believe invented it on the 70 series.
Title: Re: New EEVblog BM786 Multimeter
Post by: Specmaster on November 17, 2020, 10:40:21 pm
It is documented. REC gives you the usual Max/Min/Average values as on other multimeters.
Yes I understand that, but what I'm saying here is, that the REC is a possible workaround to the issue of autohold, unless autohold will automatically reset itself each time

AutoHold does reset itself, that's why it's called AUTOhold. Just like the original Fluke TouchHold who I believe invented it on the 70 series.
Yes, it does, I just tried the Hold function on my Fluke 27 which works perfectly.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on November 18, 2020, 12:33:22 pm
Fuse replacement seems like a bit of a nuisance for such a recently designed multimeter:
8 screws to remove the front panel and battery compartment for access to both fuses.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 18, 2020, 11:19:23 pm
Fuse replacement seems like a bit of a nuisance for such a recently designed multimeter:
8 screws to remove the front panel and battery compartment for access to both fuses.

Yes. That likely stems from design restrictions bought about by the decision to use the overmoulding to presumably look'n'feel like the Fluke 70 series.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on November 19, 2020, 06:04:34 am
Fuse replacement seems like a bit of a nuisance

That's a good thing - teaches you to not blow fuses.  :-+
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on November 19, 2020, 10:42:32 am
It might happen more often than you think, with a 400mA fuse in a 60,000 count meter.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on November 19, 2020, 11:35:31 am
It might happen more often than you think, with a 400mA fuse in a 60,000 count meter.

It depends..

Since I have DP831 and UT210E , i haven't measured current with meter that often.
When I do, I alternate between Brymens and MTX3293 (that has only one current input), and use Metrix for current measurements at desk mostly because of that. Which means I usually have no source to blow 10A fuse.

On equipment that runs lead acid accumulators, I mainly use UT210E, mostly because I don't need absolute precision and no need to disconnect wiring..

I blew exactly 3 fuses in meters in 40 years... First one, 40 years ago, scared the bejesus out of me.. Since then I'm really careful about any current measurements...  Other 2 were measuring current on equipment connected to lead acid acccu, that while measuring drew too much current..

I also pretty much never rotate meter switch with voltage connected, even if I know it's perfectly safe.. I just have bad feeling in the stomach when I think about doing it...  What can I say, childhood traumas....  :-DD
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on November 19, 2020, 01:32:44 pm
At least you don't have to then remove even more screws to pull the PCB to get at the fuses.   I tend to use other means to read current as well.   I've blown more fuses after I started looking at these handheld meters than in my entire life.   If a meter comes with glass, well, I can't resist watching them shatter.    :-DD
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on November 19, 2020, 03:27:14 pm
It might happen more often than you think, with a 400mA fuse in a 60,000 count meter.

What's the relationship between the two?

If anything, 60,000 counts should make it less likely to blow a fuse because you can work more in the amps range.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on November 19, 2020, 03:29:06 pm
It might happen more often than you think, with a 400mA fuse in a 60,000 count meter.
Yes. Despite the price of HRC cartridges, I saw myself in the situation of occasional sudden spikes in current due to failures or shorts. All low-voltage electronics, but definitely enough to kill a 44/100.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on November 19, 2020, 03:55:35 pm
It might happen more often than you think, with a 400mA fuse in a 60,000 count meter.
Yes. Despite the price of HRC cartridges, I saw myself in the situation of occasional sudden spikes in current due to failures or shorts. All low-voltage electronics, but definitely enough to kill a 44/100.
As I said, it highly depends on what you do.
MTX3293 has only one current socket and is designed to autorange from 1mA to 100A (20a constant) range at all times. It will also switch to current mode automatically if you plug cable in current socket. So to blow a fuse, you have to go over 20 for some time, or over 100A for a short time...
I quite like it...
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on November 19, 2020, 04:11:37 pm
It might happen more often than you think, with a 400mA fuse in a 60,000 count meter.

What's the relationship between the two?

If anything, 60,000 counts should make it less likely to blow a fuse because you can work more in the amps range.
The range is 600 mA, protected by a 400 mA fuse. Running 600mA for too long will blow the fuse eventually.

Notice that at 135% of its rated current a North American fuse must open
within one hour while an IEC fuse must be able to carry 150% of its rated
current for at least one hour
Cooper Bussmann
Title: Re: New EEVblog BM786 Multimeter
Post by: bitseeker on November 22, 2020, 10:19:18 pm
I guess they assume you wouldn't be measuring at full scale for extended periods of time. Nevertheless, an interesting mismatch of values.
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on November 22, 2020, 10:46:18 pm
I guess they assume you wouldn't be measuring at full scale for extended periods of time. Nevertheless, an interesting mismatch of values.

Especially when you consider that 630mA is a standard fuse value.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 22, 2020, 10:54:05 pm
I guess they assume you wouldn't be measuring at full scale for extended periods of time. Nevertheless, an interesting mismatch of values.

Very common.
The Fluke 70 and 80 series are both 6000 count and use a 440mA fuse.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on November 23, 2020, 07:02:26 am
Regardless, one needs to be careful when exceeding the fuse rated current for any length of time, especially in warm ambient condition.

I don't think Bussmann Cooper makes a 600mA fuse for Fluke multimeters, but SIBA does make a FF 630mA 1000V 32/6.3mm fuse, which would be a better match than the SIBA 400mA fuse installed at the Brymen factory.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on November 23, 2020, 07:50:43 am
Very common.
The Fluke 70 and 80 series are both 6000 count and use a 440mA fuse.

A 440mA fuse won't blow at 441mA. Fuses will often stand double their current, they just get very warm

Underrating the fuse in this way will make it much more likely to blow at the expected current (eg. 7-800mA in a 6000 count meter).

The best way was the way it used to be done, eg. the 600mA range would have a cheap 600mA glass fuse in series with an expensive 2A HRC fuse. The idea was to blow the cheap fuse in small slipups (we've all been there) but to still have HRC protection in industrial accidents.

I wonder why they stopped doing that, was it because of burden voltage?
Title: Re: New EEVblog BM786 Multimeter
Post by: Kleinstein on November 23, 2020, 08:40:30 am
There is a problem with a cheap fuse in series with the proper HRC fuse. With a DC source it is possible and not that unlikely that the cheap fuse can blow but not quench the arc, even with a current not large enough blow the higher rated HRC one. The extra heat will become a problem where the HRC fuse will not help with very much. The smaller fuse may still be OK, but should still be DC rated and thus not a really cheap one. This is kind of the price you have to pay for a CAT 3 rating.

A 440 mA fuse will likely not blow at 441 mA, but legally there is a chance it could. It usually takes more like twice the current to reliably blow the fuse, but some may bow earlier.

I see no real problem if the fuse would even well exceed the nominal range, like a 440 mA fuse in a 200 mA range, as long as the protection is up to it. Especially for the lower range a slightly larger fuse rating would be preferable and would also allow lower burden and less heat under normal conditions. However it still needs the protection (diodes) to be good for the higher current. This may need re-certification / testing and is thus not a change to be made easy.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on November 23, 2020, 12:18:18 pm
I guess they assume you wouldn't be measuring at full scale for extended periods of time. Nevertheless, an interesting mismatch of values.

Very common.
The Fluke 70 and 80 series are both 6000 count and use a 440mA fuse.
The Fluke 87 V has a a range of 400mA only, with a specified limit of 400mA continuous and overload 600mA for 18 hours.
The Fluke 179 has a range of 400mA only, with a specified limit of 600 mA overload for 2 minutes maximum, 10 minutes rest.

The Brymen 786 should have a limited mA range of 400mA, not 600mA.
Title: Re: New EEVblog BM786 Multimeter
Post by: dcac on November 23, 2020, 03:04:29 pm
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?

Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on November 23, 2020, 03:16:40 pm
Keysight 60,000 count meter manual:

Current can be measured at 440 mA continuously, and > 440 mA to 600 mA for 20
hours maximum.
To avoid blowing the multimeter’s 440 mA fuse, use the terminal only if you
are sure the current is less than 440 mA.


No warranty claim there.
Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on November 26, 2020, 03:11:59 am
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?

When has a blown fuse ever been covered  by a warranty?   
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on November 26, 2020, 08:11:52 am
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?

When has a blown fuse ever been covered  by a warranty?   

Quite.

Besides - if the fuse blew, how would they know the current they were measuring?  Might have been a steady state 590mA and blew when a transient hit.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on November 26, 2020, 08:43:41 am
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?

No.
Title: Re: New EEVblog BM786 Multimeter
Post by: Kleinstein on November 26, 2020, 09:07:43 am
Keysight 60,000 count meter manual:

Current can be measured at 440 mA continuously, and > 440 mA to 600 mA for 20
hours maximum.
To avoid blowing the multimeter’s 440 mA fuse, use the terminal only if you
are sure the current is less than 440 mA.


No warranty claim there.

A similar note should be included if the range is larger than the fuse rating.
With a warranty claim, the user could receive this missing bit of text from the instructions.  :-DD
Ideally the fuse values should be noted on the meter directly. I have seen this with some meters though there it was the usual way around, like 400 mA fuse for a 200 mA range.
One could argue to change the nominal range to the fuse rating and treat the extra range only as "over-range" for short time use. Due to thermal effect the accuracy is often anyway relatively poor at the upper end. So the specs for the reduced range could get better.
Title: Re: New EEVblog BM786 Multimeter
Post by: dcac on November 26, 2020, 01:51:08 pm
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?

No.

How about then after the third or fourth time it happens within a couple of weeks?
Title: Re: New EEVblog BM786 Multimeter
Post by: dcac on November 26, 2020, 01:52:28 pm
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?

When has a blown fuse ever been covered  by a warranty?   

Quite.

Besides - if the fuse blew, how would they know the current they were measuring?  Might have been a steady state 590mA and blew when a transient hit.

This customer was measuring the current draw from a battery through a resistor.

Are you saying 590mA is fine as long as you have absolutely zero transients.
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on November 26, 2020, 02:53:26 pm
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?

When has a blown fuse ever been covered  by a warranty?   

Quite.

Besides - if the fuse blew, how would they know the current they were measuring?  Might have been a steady state 590mA and blew when a transient hit.

This customer was measuring the current draw from a battery through a resistor.

Are you saying 590mA is fine as long as you have absolutely zero transients.

Arguably, you'd only have a warranty claim if the fuse failed to blow, and the meter or user suffered damage as a result.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 27, 2020, 06:22:58 am
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?
No.
How about then after the third or fourth time it happens within a couple of weeks?

Then the user who knowingly installed a 400mA fuse three or 4 times and still complains about it blowing at 590mA should probably stop using a multimeter and give up electronics all together.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on November 27, 2020, 07:58:07 am
How about then after the third or fourth time it happens within a couple of weeks?

PEBKAC.

(ok, it should be "PEBMAC"...  :-DMM )
Title: Re: New EEVblog BM786 Multimeter
Post by: dcac on November 27, 2020, 11:53:04 am
Will a blown 400mA fuse in BM786 be covered by the warranty - if customer claims it was only measuring 590mA when it happened?
No.
How about then after the third or fourth time it happens within a couple of weeks?

Then the user who knowingly installed a 400mA fuse three or 4 times and still complains about it blowing at 590mA should probably stop using a multimeter and give up electronics all together.

My mistake - I just noticed the print next to the uA/mA input jack actually says Max 0.6A and not only 0.6A. And i.e. BM869s does the same but it has at least a 440mA fuse so slightly more margin if you interpret it as 0.6A 'continuous' current.

Edit: that's actually not true either as BM786 might have a different perhaps slower type fuse.
 
Title: Re: New EEVblog BM786 Multimeter
Post by: dcac on November 27, 2020, 02:39:40 pm
It seems the Bussmann 440mA fuse used in BM869s if often called 0.4A fuse. Bussmann doesn’t seem to have any 400mA rated fuse - but i.e. Siba does and have both 400mA and 440mA types.

In the datasheet for Bussmann (0.4A)/0.44A fuse it states ” Intended to carry 100% of rated current indefinitely." Looking at the characteristics curve it can handle about 1.2A for 300 seconds - beyond that time is not shown perhaps due to possible fatiguing coming into play.

https://www.elfa.se/Web/Downloads/_t/ds/DMM-B_eng_tds.pdf (https://www.elfa.se/Web/Downloads/_t/ds/DMM-B_eng_tds.pdf)
Title: Re: New EEVblog BM786 Multimeter
Post by: Invenis on November 29, 2020, 10:11:57 pm
I was just about to pull a trigger on 869s and that came up :o What a nice multimeter! The LoZ, AutoHold, NCV and BeepLit. Now I'm trying to decide which one to get  :-// Also I wonder whether Brymen has some kind of refreshed version of 869s in the works.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on November 30, 2020, 02:46:52 am
Also I wonder whether Brymen has some kind of refreshed version of 869s in the works.

Not that I am aware of.
Title: Re: New EEVblog BM786 Multimeter
Post by: xavier60 on December 01, 2020, 08:58:26 am
Really nice. I have some questions:
Does it work well with rechargeable AAA batteries?
Does it come with a Cal certificate?

It should work ok with rehcargables:
https://www.eevblog.com/forum/testgear/us (https://www.eevblog.com/forum/testgear/us)$150-class-multimeter/msg3077681/#msg3077681
No cal certificate, just like other Brymens.
Well, 3.55V/3= 1.18V. That is around 50% DoD of a NiMH, so not perfect.
I guess we buy a pack of alkaline then.
If there is a problem with NiMh, then I wonder why only 3 cells when 4 is a more convenient quantity and would have very likely eliminated possible NiMh problems, space permitting.
Ill be finding out for myself.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on December 01, 2020, 12:12:00 pm
Really nice. I have some questions:
Does it work well with rechargeable AAA batteries?
Does it come with a Cal certificate?

It should work ok with rehcargables:
https://www.eevblog.com/forum/testgear/us (https://www.eevblog.com/forum/testgear/us)$150-class-multimeter/msg3077681/#msg3077681
No cal certificate, just like other Brymens.
Well, 3.55V/3= 1.18V. That is around 50% DoD of a NiMH, so not perfect.
I guess we buy a pack of alkaline then.
If the there is a problem with NiMh, then I wonder why only 3 cells when 4 is a more convenient quantity and would have very likely eliminated possible NiMh problems, space permitting.
Ill be finding out for myself.

Not enough depth, it uses a new design vertical holder.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on December 01, 2020, 12:18:44 pm
The batteries are in a carrier that separates from the meter.  The three batteries are mounted side by side and the pack is perpendicular to the PCB.  The batteries themselves are located towards the very top most part of the meter.  The packs height sets the thickness of the meter.  It's well laid out, making use of every bit of space.   Using this technique while adding a fourth battery would make for a thicker or a taller meter.

Slow on the draw today...
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on December 01, 2020, 02:02:50 pm
The batteries are in a carrier that separates from the meter.  The three batteries are mounted side by side and the pack is perpendicular to the PCB.  The batteries themselves are located towards the very top most part of the meter.  The packs height sets the thickness of the meter.  It's well laid out, making use of every bit of space.   Using this technique while adding a fourth battery would make for a thicker or a taller meter.

Slow on the draw today...
A picture is worth 78 words...  :-DD
Title: Re: New EEVblog BM786 Multimeter
Post by: coromonadalix on December 01, 2020, 08:19:42 pm
you miss the other 922 words    :-DD,   nice pack design, or maybe 3d print another one with the batteries rotated in it, to acomodate a longer cell ??
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on December 01, 2020, 09:37:03 pm
This battery compartment design seems to protect meter electronics from battery leakage if meter is stored both face down and back down... Nice..
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on December 02, 2020, 03:57:12 am
The batteries are in a carrier that separates from the meter.  The three batteries are mounted side by side and the pack is perpendicular to the PCB.  The batteries themselves are located towards the very top most part of the meter.  The packs height sets the thickness of the meter.  It's well laid out, making use of every bit of space.   Using this technique while adding a fourth battery would make for a thicker or a taller meter.

Slow on the draw today...
A picture is worth 78 words...  :-DD
The way I type, it may have been faster too!
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on December 02, 2020, 10:36:55 am
Really nice. I have some questions:
Does it work well with rechargeable AAA batteries?
Does it come with a Cal certificate?

It should work ok with rehcargables:
https://www.eevblog.com/forum/testgear/us (https://www.eevblog.com/forum/testgear/us)$150-class-multimeter/msg3077681/#msg3077681
No cal certificate, just like other Brymens.
Well, 3.55V/3= 1.18V. That is around 50% DoD of a NiMH, so not perfect.
I guess we buy a pack of alkaline then.

Or use Ni-Zn cells?
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on December 02, 2020, 11:25:27 am
I guess we buy a pack of alkaline then.

...and let them leak!  :scared:

The real question should be "Does it work with Eneloops"?
Title: Re: New EEVblog BM786 Multimeter
Post by: MiroS on December 02, 2020, 05:54:38 pm
I guess we buy a pack of alkaline then.

...and let them leak.

The real question should be "Does it work with Eneloops"?

Good point. I am moving all to rechargeable batteries , no 'Eneloop' means for me  'pass by /  not to  buy'
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on December 03, 2020, 06:38:34 pm
I guess we buy a pack of alkaline then.

...and let them leak.

The real question should be "Does it work with Eneloops"?

Good point. I am moving all to rechargeable batteries , no 'Eneloop' means for me  'pass by /  not to  buy'

Mi-MH is not the only rechargeable chemistry. Not buying something because it doesn't work with Eneloops is cutting off your nose to spite your face.

Ni-Zn have a nominal cell voltage of 1.6, though are 1.85-1.9 when freshly charged. I use them in my Fluke 289 with no ill effects.

Li-ion are an alternative also; you can get 1.5V AA cells, which have built in chargers, running of usb, or you can get AA sized cells with the usual 3.7V and use dummy AA's to match the voltage you want.

Personally I prefer the Ni-Zn as they are a variation on the existing and well understood nickel secondary cell. I'm still wary of using Li-ion in something I couldn't/wouldn't be happy to throw out of the window if things went wrong.
Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on December 26, 2020, 01:55:31 am
Man this thread was hard to find.   

In any event is this meter still on as a coming new product.   It has been a few weeks and I've heard nothing.   

Maybe some of the other manufactures are getting jealous and are offering Dave new meters to plant the EEVBlog label on.  Yes wishful thinking but hey it is Christmas.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on December 26, 2020, 09:24:46 am
Man this thread was hard to find.   
In any event is this meter still on as a coming new product.   It has been a few weeks and I've heard nothing.   

I just paid for my stock, so I guess it's coming shortly.


Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on December 26, 2020, 11:05:16 am
Ahhhh....

Let us know when you have a price.
Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on December 26, 2020, 02:39:53 pm
Man this thread was hard to find.   
In any event is this meter still on as a coming new product.   It has been a few weeks and I've heard nothing.   

I just paid for my stock, so I guess it's coming shortly.

So are taxes, I guess it will be RAMEN noodles all January.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on December 26, 2020, 05:04:17 pm
Normally, when a new product comes out, I tend to give it some time while the company sorts out some kinks.   In this case, after spending a couple of months evaluating the meter and working with Brymen to make some improvements before its release, I'm looking forward to hearing what the first owners think of it.
Title: Re: New EEVblog BM786 Multimeter
Post by: TheAmmoniacal on December 26, 2020, 09:26:03 pm
Might be a bit off-topic, but which meter has the fasted continuity tester now? Is the BM786 in par with Fluke?
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on December 26, 2020, 10:20:34 pm
Might be a bit off-topic, but which meter has the fasted continuity tester now? Is the BM786 in par with Fluke?

Are all Fluke products the same?

With no other constraints, I think the UT90A may still be one of the fasted.   

https://www.youtube.com/watch?v=svJXiMMZzcQ (https://www.youtube.com/watch?v=svJXiMMZzcQ)
Title: Re: New EEVblog BM786 Multimeter
Post by: Pampalini on December 27, 2020, 12:14:10 pm
BM780 Series (http://www5.biall.com.pl/BAZA_PRODUKTOW_SMB/102222/102222.KARTA_EN..2020-10-26.1.pdf) - BM785 / BM789 leaflet

Prices in BIALL (excluding VAT)So this prices seems to be slightly lower than in Welectron. This are list prices, retail prices may be even lower.
Both product are not available yet.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on December 29, 2020, 06:19:03 am
Shipping around Dec 31st. That leaves very little time to get here, me to check things before I leave on the 8th Jan. But I should have them in hand before I leave at least.
Can probably take pre-orders in anticipation and then Suse my logistics person can ship them while I'm away.
Title: Re: New EEVblog BM786 Multimeter
Post by: rernexy on December 29, 2020, 06:22:58 am
.....
Can probably take pre-orders in anticipation...
Right now ?!!
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on December 29, 2020, 11:10:45 am
Now shipping tomorrow, partial delivery though, supply issues.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on December 30, 2020, 10:13:27 am
Cutting it fine, I'm away on the 8th
BTW, no more import custom delays and double handling now that I use my DHL account for all imports, way better.
(https://www.eevblog.com/forum/testgear/new-eevblog-bm786-multimeter/?action=dlattach;attach=1141688;image)

Title: Re: New EEVblog BM786 Multimeter
Post by: Muttley Snickers on December 30, 2020, 11:14:46 am
Any idea on which leads are going to be supplied with these meters ?   :-DMM

And will a case, crocodile clips or magnetic hanger also be available ?   :-DMM

Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on December 30, 2020, 12:01:27 pm
Any idea on which leads are going to be supplied with these meters ?   :-DMM
And will a case, crocodile clips or magnetic hanger also be available ?   :-DMM

The Brymen silicone leads as per BM235.
No plans for the accesories at this stage.
Title: Re: New EEVblog BM786 Multimeter
Post by: pinback on December 30, 2020, 05:49:03 pm
Dave, I have two of your earlier DMMs, and enjoy using them. Do you think you'll qualify a capacitance/ESR meter at some point? Its another piece of kit that SME review would make me feel more confident in purchasing.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on December 31, 2020, 04:28:03 am
Dave, I have two of your earlier DMMs, and enjoy using them. Do you think you'll qualify a capacitance/ESR meter at some point? Its another piece of kit that SME review would make me feel more confident in purchasing.

No major plans in that area.
If anyone knows of any decent test gear that isn't being marketing or distributed well, let me know though. I do want to expand the product portfolio.
Title: Re: New EEVblog BM786 Multimeter
Post by: symp on January 04, 2021, 03:24:48 am
Soooo, any chance of putting in a pre-order? Also, is there a rough ETA for more 121GW stock?

Cheers
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 05, 2021, 01:26:02 am
They arrived!

(https://pbs.twimg.com/media/Eq7a8cJVQAAsDfx?format=png&name=900x900)

I guess they are version 5, they old prototype shows 1
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 05, 2021, 02:05:51 am
Looks like you have all the latest updates.  Five was the last firmware version I tested.   We covered a lot of ground in the last few months. I certainly didn't treat it with kid gloves during that time.    Take out for a spin and let us know what you think of it. 
Title: Re: New EEVblog BM786 Multimeter
Post by: Muttley Snickers on January 05, 2021, 02:06:50 am
They arrived!

Do these meters come with bullshit or no-bullshit packaging ?   ???
Title: Re: New EEVblog BM786 Multimeter
Post by: bc888 on January 05, 2021, 02:24:21 am
They arrived!

Do these meters come with bullshit or no-bullshit packaging ?   ???

Muttly, you need to put up a pic or few will get the joke unless they bought Daves earlier home run Evblog BM235. It was reminicent of the old generic packaging in the US where black text on a white package announced what was inside. Example: BEER on a 12 pack of beer. (That was most of it). I would have been an  early adopter but son-in-law to be got a used (but well within spec) Fluke 189 II with a link to the capacitor issue on Eevblog instead.

Now I can wait till it shakes out and get Daves Gen 2 789. Have a good road trip Dave, and Joe Smith, thank you for some great reads/watches. 
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 05, 2021, 03:07:36 am
Looks like you have all the latest updates.  Five was the last firmware version I tested.   We covered a lot of ground in the last few months. I certainly didn't treat it with kid gloves during that time.    Take out for a spin and let us know what you think of it.

Thanks.
Don't have time unfortunately. Will barely to able to get this listed and ready for shipment before I leave on holidays in a few days. So many people will be using the latest version before me...
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 05, 2021, 03:08:25 am
They arrived!
Do these meters come with bullshit or no-bullshit packaging ?   ???

No bullshit!

(https://pbs.twimg.com/media/Eq7dnV-UwAEQ0SK?format=jpg&name=medium)
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on January 05, 2021, 03:34:16 am
I think I should have licenced that graphic rather than giving it away.  (Though Dave did send me an unexpected - and good value - consideration for it, back when first created.)

Nice to see it still lives on, though.   :-+
Title: Re: New EEVblog BM786 Multimeter
Post by: symp on January 05, 2021, 06:10:17 am
Ordered....hopefully it's even better than the BM235 has been

Any ETA for 121GW stock?
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 05, 2021, 06:52:01 am
Any ETA for 121GW stock?

No exact date. Likely March.
Title: Re: New EEVblog BM786 Multimeter
Post by: fabrizio_fabrice on January 05, 2021, 07:00:20 pm
I guess we buy a pack of alkaline then.

...and let them leak.

The real question should be "Does it work with Eneloops"?

Good point. I am moving all to rechargeable batteries , no 'Eneloop' means for me  'pass by /  not to  buy'

Mi-MH is not the only rechargeable chemistry. Not buying something because it doesn't work with Eneloops is cutting off your nose to spite your face.

Ni-Zn have a nominal cell voltage of 1.6, though are 1.85-1.9 when freshly charged. I use them in my Fluke 289 with no ill effects.

Li-ion are an alternative also; you can get 1.5V AA cells, which have built in chargers, running of usb, or you can get AA sized cells with the usual 3.7V and use dummy AA's to match the voltage you want.

Personally I prefer the Ni-Zn as they are a variation on the existing and well understood nickel secondary cell. I'm still wary of using Li-ion in something I couldn't/wouldn't be happy to throw out of the window if things went wrong.

Yes, that's reasonable if you have only one device to power, don't mind the customization, or the need to keep another battery type on hand. 

But I'm with MiroS - I use Eneloops in significant numbers, kinds and types of devices where any other single approach would not be practical.  For me, the solution is to have a decent NiMH charger (thanks, HKJ  :-+  http://www.lygte-info.dk (http://www.lygte-info.dk)) and keep 1 more set of Eneloops than needed on-hand, fully-charged. 

I'm a fan of '60s Telefunken portables and use adapters to convert them from 5 D-cells to AA Eneloops.  Used about an hour a day in a home environment [not full-blast - they'll output 2.5W**], they last ~ 2 mo on a charge.  And it makes the radio so much lighter to carry around.

So yes, I was glad to see I can also use NiMH in this meter, and won't mind a bit if it won't run down to the dead battery limit.  Besides, more recharge cycles that way, too.

[**You know, I should try 'full blast' sometime; they'll probably sound pretty good since Eneloops won't droop under the current load.]
Title: Re: New EEVblog BM786 Multimeter
Post by: Andrew McNamara on January 06, 2021, 01:18:56 am
If anyone knows of any decent test gear that isn't being marketing or distributed well, let me know though. I do want to expand the product portfolio.

What about a clamp meter like the BM065? Not as cheap as the UT210E, but I'd prefer the Brymen.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 06, 2021, 04:17:09 am
$123 for the 235 and only $150 for this?!  It doesn't seem like a bad price.  The Fluke 115 is over $180 and not near as useful.   
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on January 06, 2021, 04:31:12 am
I guess we buy a pack of alkaline then.

...and let them leak.

The real question should be "Does it work with Eneloops"?

Good point. I am moving all to rechargeable batteries , no 'Eneloop' means for me  'pass by /  not to  buy'

Mi-MH is not the only rechargeable chemistry. Not buying something because it doesn't work with Eneloops is cutting off your nose to spite your face.

Ni-Zn have a nominal cell voltage of 1.6, though are 1.85-1.9 when freshly charged. I use them in my Fluke 289 with no ill effects.

Li-ion are an alternative also; you can get 1.5V AA cells, which have built in chargers, running of usb, or you can get AA sized cells with the usual 3.7V and use dummy AA's to match the voltage you want.

Personally I prefer the Ni-Zn as they are a variation on the existing and well understood nickel secondary cell. I'm still wary of using Li-ion in something I couldn't/wouldn't be happy to throw out of the window if things went wrong.

Yes, that's reasonable if you have only one device to power, don't mind the customization, or the need to keep another battery type on hand. 

But I'm with MiroS - I use Eneloops in significant numbers, kinds and types of devices where any other single approach would not be practical.  For me, the solution is to have a decent NiMH charger (thanks, HKJ  :-+  http://www.lygte-info.dk (http://www.lygte-info.dk)) and keep 1 more set of Eneloops than needed on-hand, fully-charged. 

I'm a fan of '60s Telefunken portables and use adapters to convert them from 5 D-cells to AA Eneloops.  Used about an hour a day in a home environment [not full-blast - they'll output 2.5W**], they last ~ 2 mo on a charge.  And it makes the radio so much lighter to carry around.

So yes, I was glad to see I can also use NiMH in this meter, and won't mind a bit if it won't run down to the dead battery limit.  Besides, more recharge cycles that way, too.

[**You know, I should try 'full blast' sometime; they'll probably sound pretty good since Eneloops won't droop under the current load.]

Ni-Zn are no more expensive than Ni-MH, they just have a lower mAH capacity, though obviously this is offset somewhat by the higher nominal cell voltage. Overall they're probably around 10% lower in terms of mWH.
I use them in my Fluke 289 with no modifications, YMMV, you just have to suck it and see.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 06, 2021, 04:45:55 am
$123 for the 235 and only $150 for this?!

I've been saying for a year now that I was going to offer a $150 class meter, why the surprise?
But of course that doesn't include shipping, and price will vary depending on where you get it from (Simon's Electronics, Welectron, Amazon (which is me))
Might have to reevaluate the BM235 price, but it is still significantly cheaper, and many people like myself just prefer the smaller meter.

Quote
The Fluke 115 is over $180 and not near as useful.

Yes, it blows the Flukes out of the water, including of course the 70 series it's obviously designed to compete with in look'n'feel.
Title: Re: New EEVblog BM786 Multimeter
Post by: LarryS on January 06, 2021, 04:33:18 pm
Dave does not have a reply banner on his posts.  Thus, I could not "wish' he did have a LCR-ESR meter in his portfolio.

As to a LCR - ESR meter, I have a DER EE DE-5000 for which I bought BK Precision TL8KC1 Kelvin leads as the leads that come with the meter are a piece of s**t.  There is a gentleman on the this blog who has remarkable skills with mechanical things and made his own Kelvin leads for the meter.  I do not have either the tools no the skill to make what he did - he made a video of is effort.  In any event, the TL8KC1 leads work very well though I'm sure not as near perfect as the gentleman in question.

I wish the 'meter tester gentleman' (joesmith)would do a test of the various LCR-ESR meters out there.

Again to the 'meter tester gentleman', did you make the box that seemingly has an infinite number of test terminals to do his testing?

Thank you,         larry
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 06, 2021, 05:39:36 pm
$123 for the 235 and only $150 for this?!

I've been saying for a year now that I was going to offer a $150 class meter, why the surprise?
But of course that doesn't include shipping, and price will vary depending on where you get it from (Simon's Electronics, Welectron, Amazon (which is me))
Might have to reevaluate the BM235 price, but it is still significantly cheaper, and many people like myself just prefer the smaller meter.
As I mentioned during the last video,  I'm just surprised that the BM235's price did not drop.   No doubt the 235 is very robust but outside of using it for some basic electrical work, I wouldn't have a use for it.  With only a $25 spread, I would hands down buy the 786. 

Quote
The Fluke 115 is over $180 and not near as useful.

Yes, it blows the Flukes out of the water, including of course the 70 series it's obviously designed to compete with in look'n'feel.

Outside of the vintage Fluke 189 and 97, I don't use any of their other products.  Not that they are over priced and they are certainly one of the most robust brands I have looked at, they just don't offer products that are a good fit feature wise for me.  If I were a technician or electrical worker, it would be a totally different story.   The 78x series fills a void IMO for people wanting a robust well built meter with some basic features for electronics but can't afford $200+.   
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 06, 2021, 05:49:12 pm
...
I wish the 'meter tester gentleman' (joesmith)would do a test of the various LCR-ESR meters out there.

Again to the 'meter tester gentleman', did you make the box that seemingly has an infinite number of test terminals to do his testing?
...

I'll leave the scopes, signal generators, power supplies and LCR meters to the other reviewers.  Outside of reading the manual, I'm not sure what I would have to offer for an LCR meter.   It's not a device I am expecting someone is damaging with normal use. 

Yes, that box is something I put together to partially determine if a meter has been damaged during my testing.   It contains an APEX reference and several Caddock SVD2  parts.  Not good enough for a standard but more than good enough to see if a meter is starting to deviate.  It's changed over time to increase the number of tests I can quickly rifle through. 
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on January 06, 2021, 05:53:23 pm
$123 for the 235 and only $150 for this?!

I've been saying for a year now that I was going to offer a $150 class meter, why the surprise?
But of course that doesn't include shipping, and price will vary depending on where you get it from (Simon's Electronics, Welectron, Amazon (which is me))
Might have to reevaluate the BM235 price, but it is still significantly cheaper, and many people like myself just prefer the smaller meter.
As I mentioned during the last video,  I'm just surprised that the BM235's price did not drop.   No doubt the 235 is very robust but outside of using it for some basic electrical work, I wouldn't have a use for it.  With only a $25 spread, I would hands down buy the 786. 

Quote
The Fluke 115 is over $180 and not near as useful.

Yes, it blows the Flukes out of the water, including of course the 70 series it's obviously designed to compete with in look'n'feel.

Outside of the vintage Fluke 189 and 97, I don't use any of their other products.  Not that they are over priced and they are certainly one of the most robust brands I have looked at, they just don't offer products that are a good fit feature wise for me.  If I were a technician or electrical worker, it would be a totally different story.   The 78x series fills a void IMO for people wanting a robust well built meter with some basic features for electronics but can't afford $200+.   

Well said. And now it has all the features Fluke users complained about  as "must haves": diode test mode, auto hold, and some other details..
Title: Re: New EEVblog BM786 Multimeter
Post by: fabrizio_fabrice on January 06, 2021, 11:05:38 pm
Quote
Ni-Zn are no more expensive than Ni-MH, they just have a lower mAH capacity, though obviously this is offset somewhat by the higher nominal cell voltage. Overall they're probably around 10% lower in terms of mWH.
I appreciate you mentioning these, I wasn't familiar with them.  I got suspicious when I saw the change in rating method.  HKJ wrote they specify in Wh, "probably to hide the fact that they has less capacity than NiMH batteries".

What is the advantage of higher cell voltage if used in a device like the BM786, if it down-regulates to 3.5 v?  If they have less total capacity, the higher voltage wouldn't translate into better run-time. 

OTOH, if you have drones, their better energy density would be a real help!

There's a discrepancy between Wikipedia: "they can be discharged to almost 100%, and recharged without problems"  vs. HKJ's statement that they have a rather short lifetime because "they are over discharged when used as replacement for alkaline or NiMH cells."  What's the reality?   Over-discharging is particularly likely if they're down to near-zero by the time the device begins to noticeably misbehave.   

I agree about Li-I,but it's not about throwing them away.  It's about my home going up in flame. I want to buy from a reputable company with lots to lose.  Even so, Samsung had to get stung, first, didn't they?

I don't know how to fairly compare costs. Can you recommend a brand that has established a reputation for reliability and durability that's comparable to Eneloops?
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 06, 2021, 11:18:44 pm
What is the advantage of higher cell voltage if used in a device like the BM786, if it down-regulates to 3.5 v?  If they have less total capacity, the higher voltage wouldn't translate into better run-time. 

There is very little capacity in the higher terminal voltage batteries at the high voltage point, the voltage drops pretty quickly under load.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 06, 2021, 11:23:28 pm
Dave does not have a reply banner on his posts.  Thus, I could not "wish' he did have a LCR-ESR meter in his portfolio.

I'd like one, but it's hard find something good without an already well established distribution chain and low prices.
Brymen works because they have pretty horrible marketing and distribution in a lot fo the world, and the margins are good, so they are winners for me.
If anyone knows of a suitable one on the market please let me know, I do want to expand my product portfolio.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 06, 2021, 11:29:11 pm
As I mentioned during the last video,  I'm just surprised that the BM235's price did not drop.   No doubt the 235 is very robust but outside of using it for some basic electrical work, I wouldn't have a use for it.  With only a $25 spread, I would hands down buy the 786.

Sure but everyones needs are different.
When I list the BM786 on amazon I'll see if the BM235 sales drop, if they do then I'll adjust the price. I sell a ton of BM235 on amazon. Could actually take the BM786 substantial time to build up the same search ranking.

Quote
The 78x series fills a void IMO for people wanting a robust well built meter with some basic features for electronics but can't afford $200+.   

Yep, that's what I thought too when they first proposed it. I'm fairly confident it'll be a winner. Have just ordered another batch.
FYI Brymen pitched me the BM836/839 and sent me samples but I turned those down as they didn't have the same value proposition, so I waited an extra year for the BM786
Title: Re: New EEVblog BM786 Multimeter
Post by: BU508A on January 06, 2021, 11:39:00 pm
If anyone knows of any decent test gear that isn't being marketing or distributed well, let me know though. I do want to expand the product portfolio.

Dave, I've forwarded your request to the TEA thread. Maybe those folks have some ideas ...  ;D  ;D

https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg3403880/#msg3403880 (https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg3403880/#msg3403880)
Title: Re: New EEVblog BM786 Multimeter
Post by: BU508A on January 07, 2021, 12:05:04 am
Dave does not have a reply banner on his posts.  Thus, I could not "wish' he did have a LCR-ESR meter in his portfolio.

I'd like one, but it's hard find something good without an already well established distribution chain and low prices.
Brymen works because they have pretty horrible marketing and distribution in a lot fo the world, and the margins are good, so they are winners for me.
If anyone knows of a suitable one on the market please let me know, I do want to expand my product portfolio.

I'm not sure if this is a good idea, but how about the DER EE DE-5000 LCR meter? If one wants to buy one new, one has to order it in Japan, e.g. via ebay sellers from there. There is nearly no marketing for them e.g. in Europe.

Just as an idea, probably a stupid one.
Title: Re: New EEVblog BM786 Multimeter
Post by: fabrizio_fabrice on January 07, 2021, 12:30:26 am
What is the advantage of higher cell voltage if used in a device like the BM786, if it down-regulates to 3.5 v?  If they have less total capacity, the higher voltage wouldn't translate into better run-time. 

There is very little capacity in the higher terminal voltage batteries at the high voltage point, the voltage drops pretty quickly under load.
Does the meter benefit in any way from a higher cell voltage? ???
Title: Re: New EEVblog BM786 Multimeter
Post by: IanB on January 07, 2021, 12:31:32 am
many people like myself just prefer the smaller meter

With aging eyesight I find I need a magnifier to use small format meters like the 235. I find big meters like the 869 much more comfortable to use  :P
Title: Re: New EEVblog BM786 Multimeter
Post by: IanB on January 07, 2021, 12:34:38 am
Does the meter benefit in any way from a higher cell voltage? ???

It depends. You do have to be a little bit careful though. The NiZn chemistry starts out at 1.8 V or higher when freshly charged and some devices may not work properly at such a high voltage.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 07, 2021, 02:24:33 am
many people like myself just prefer the smaller meter
With aging eyesight I find I need a magnifier to use small format meters like the 235. I find big meters like the 869 much more comfortable to use  :P

Err, the BM235 has the same size display as the 869.
Title: Re: New EEVblog BM786 Multimeter
Post by: J-R on January 07, 2021, 05:00:47 am
Actually, the digits on the BM235 are larger than the BM869!
Title: Re: New EEVblog BM786 Multimeter
Post by: IanB on January 07, 2021, 06:01:32 am
Err, the BM235 has the same size display as the 869.

That's true. It was actually the labels around the rotary switch of the 121GW that I found quite small, and I misremembered which meter I was thinking of.
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on January 07, 2021, 06:19:27 am
Does the meter benefit in any way from a higher cell voltage? ???

It depends. You do have to be a little bit careful though. The NiZn chemistry starts out at 1.8 V or higher when freshly charged and some devices may not work properly at such a high voltage.

I mentioned the Ni-Zn chemistry purely for when Ni-MH don't work due to low voltage. As Dave has already stated the 786 works fine with Ni-MH so there would be no advantage.

I run my 289 on Ni-Zn purely because I wanted to see if it would. I'm confident it would work as well with Ni-MH, preferably an LSD type like Eneloop etc.

Personally I like the Hobby King Turnigy brand for the simple reason they are pretty cheap, and reliable in terms of quality. I have found their Ni-MH LSD AA cells to be above rated capacity, haven't measured the Ni-Zn yet.

I would guess most modern battery devices to be designed with one eye on the Ni-MH cell voltage, so Ni-Zn is pretty niche really, mostly useful for older devices that don't like the low nominal Ni-MH/Cd cell voltage.
Title: Re: New EEVblog BM786 Multimeter
Post by: cschun86 on January 07, 2021, 11:13:52 am
Is it sold out? Eevblog store stated sold out. Couldn't find it on Amazon as well.
Can only find it on welectron at the moment.

Any place else I can purchase it? I don't really want to get it shipped from UK/Euro all the way to New Zealand.
Thanks.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 07, 2021, 11:54:13 am
Is it sold out? Eevblog store stated sold out. Couldn't find it on Amazon as well.
Can only find it on welectron at the moment.
Any place else I can purchase it? I don't really want to get it shipped from UK/Euro all the way to New Zealand.
Thanks.

Sorry, had to shut down my store for while, I'm on holidays. No stock sent to amazon yet. Simons Electronics will have some shortly but he's in the UK.
Title: Re: New EEVblog BM786 Multimeter
Post by: NuclearMusket on January 07, 2021, 10:46:51 pm
Thanks Dave, great meter. Just got my mine in today via DHL.
No trouble with it at all yet.
It does seem to be a quite a bit shorter than it appeared on camera, but maybe I'm just used to the oversized American brands...  :-DD
Title: Re: New EEVblog BM786 Multimeter
Post by: jknightandkarr on January 09, 2021, 05:28:14 am
Sorry, had to shut down my store for while, I'm on holidays. No stock sent to amazon yet. Simons Electronics will have some shortly but he's in the UK.
That explains things, when might the store be available for orders again?  I really have been wanting a 121gw dmm for a good while and finally have the cash for it.  I got one decent one, I think, but really want a nice one I can trust.  In school for electronics engineering and do hobby stuff as well.  Always enjoy watching your channel!

Joe
Title: Re: New EEVblog BM786 Multimeter
Post by: symp on January 09, 2021, 09:58:42 am
Thanks Dave, great meter. Just got my mine in today via DHL.
No trouble with it at all yet.
It does seem to be a quite a bit shorter than it appeared on camera, but maybe I'm just used to the oversized American brands...  :-DD

Australia post at it's finest....I'm 400km from Dave in the same state and don't expect it until Monday.  :-DD

Edit: arrived safely, solid meter, auto hold is nice, think I'll miss is the LoZ mode compared to the 237 though, might get the 789 next time. I should of checked my old email, had the pre public link and a coupon in there, could of saved $15 for lunch! Haha
Title: Re: New EEVblog BM786 Multimeter
Post by: bibz on January 11, 2021, 12:05:29 pm
Got mine today, nice display and ohms beepy is also great. First upgrade from a jaycar/chinesey meter and I feel this is the perfect price point for me, so thanks Dave! Cant wait to poke some stuff with it
Title: Re: New EEVblog BM786 Multimeter
Post by: Roger Need on January 15, 2021, 08:58:03 pm
I ordered my Brymen 786 on January 5 and it was shipped by DHL to Canada the next day.  Shipping was $30 Cdn. ($24 USD) for express delivery.  The package arrived 8 days later after a payment of $42 Cdn. ($31 USD) to DHL for Cdn. taxes, duties and the processing fee.  Everything was in great shape. 

I thought readers might want to know what comes in the "No BS Box" so I took some pictures of the meter and the accessories.  Batteries are not included but I never like the unknown brand that usually comes with Asian products.  It was nice to see that banana plug adapters come with the test leads and that standard alligator clips slide on easily.

I have been putting the meter through quite a few tests.  The RMS accuracy with different waveforms (sine, triangle, square wave etc.) and DC offsets is very good.   The Amps current range with 50,000 counts means I only have to use the ma. range, with the higher burden voltage, if I really need more than 3 digits.  The only drawback I have seen is that it does not have enough range to measure capacitors under 100 pF but my DE-5000 is used for that anyway.

Title: Re: New EEVblog BM786 Multimeter
Post by: Roger Need on January 15, 2021, 09:02:10 pm
Here is a photo with the battery holder removed.  Are the pins shown for flashing firmware??

Roger
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 16, 2021, 07:40:48 am
Here is a photo with the battery holder removed.  Are the pins shown for flashing firmware??

I believe they are, but Brymen don't want any (including me) to have the programmer or the details.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 16, 2021, 07:43:47 am
It does seem to be a quite a bit shorter than it appeared on camera, but maybe I'm just used to the oversized American brands...  :-DD

I think I posted a photo of it compared to some other meters some time back, will try and find it again.
Title: Re: New EEVblog BM786 Multimeter
Post by: NY2KW on January 16, 2021, 02:49:47 pm
How fast is the Autorange?
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 16, 2021, 04:52:40 pm
Here is a photo with the battery holder removed.  Are the pins shown for flashing firmware??

Roger

I was guessing that connector allowed them to perform the alignment semi-automatically.  There appears to be two other unpopulated connectors which I was guessing were for development and not needed once they got into production.   During my evaluation, any changes the to firmware required that I change ICs.   

Hopefully the majority of the problems have now been corrected and there will be little need for additional firmware changes. 

Just a quick check, the unpopulated 4-pin connector with the two pairs of common pins is on the back side of U20 and ground, used to power the meter during development or provide power to some peripheral. 

The other unpopulated connector is not in parallel with the one you asked about.   It's possible that these two unpopulated connectors were both intended to control an add-on peripheral rather than development.  The LCD is far enough away that there is certainly room to add something but with the lack of mounting holes in this area, my guess is they are both for development.   Probing the two connectors,  I didn't see anything while trying different modes.   
Title: Re: New EEVblog BM786 Multimeter
Post by: Roger Need on January 16, 2021, 07:02:04 pm
How fast is the Autorange?

I suggest you take a look at joeqsmith's excellent Youtube videos on the latest firmware with autoranging.

https://www.youtube.com/watch?v=Vgmf4mgDyHE (https://www.youtube.com/watch?v=Vgmf4mgDyHE)

Roger
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on January 16, 2021, 07:33:00 pm
Here is a photo with the battery holder removed.  Are the pins shown for flashing firmware??

Roger

I was guessing that connector allowed them to perform the alignment semi-automatically.  There appears to be two other unpopulated connectors which I was guessing were for development and not needed once they got into production.   During my evaluation, any changes the to firmware required that I change ICs.   
Despite they asked you to switch ICs, this may be due simply to the fact the devices have their JTAG port cut off to protect the Flash contents against prying eyes. This may still be used for flash programming (and perhaps some basic testing) during production.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 16, 2021, 08:19:00 pm
Here is a photo with the battery holder removed.  Are the pins shown for flashing firmware??

Roger

I was guessing that connector allowed them to perform the alignment semi-automatically.  There appears to be two other unpopulated connectors which I was guessing were for development and not needed once they got into production.   During my evaluation, any changes the to firmware required that I change ICs.   
Despite they asked you to switch ICs, this may be due simply to the fact the devices have their JTAG port cut off to protect the Flash contents against prying eyes. This may still be used for flash programming (and perhaps some basic testing) during production.

It's possible.  I didn't ask.  I did however offer to program them to avoid the shipping times and speed up our progress.   We may have saved a few weeks.  Then again, getting everything setup and working may have been more trouble than it was worth.  Not a big deal one way or the other.   It's not the 121GW.  While Dave's UEI meter still has some firmware problems noted with the prototype back in 2017,  the Brymen BM786 even though it's a brand new product, is much more mature (not to mention the quality of the parts and design).   The UEI meter needed that crutch.  I don't see that being the case with most high quality meters. 

My tests certainly are not the end all of tests but I am interested to see what problems early buyers find.  It may point to the need to improve or add to my own tests. 
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on January 16, 2021, 08:43:11 pm
While Dave's UEI meter still has some firmware problems noted with the prototype back in 2017,  the Brymen BM786 even though it's a brand new product, is much more mature (not to mention the quality of the parts and design).   The UEI meter needed that crutch.  I don't see that being the case with most high quality meters. 
UEI's core business is not on multimeters, but Brymen's is. For them it is make it or break it. For UEI, it is another department.

IIRC, shortly before the release of the 121GW UEI had discontinued their entire range of DMMs. Nowadays I see four models (https://www.ueitest.com/Ecommerce/category/products/multimeters), all 4000/6000 counts clearly for industrial markets.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 16, 2021, 11:51:21 pm
While Dave's UEI meter still has some firmware problems noted with the prototype back in 2017,  the Brymen BM786 even though it's a brand new product, is much more mature (not to mention the quality of the parts and design).   The UEI meter needed that crutch.  I don't see that being the case with most high quality meters. 
UEI's core business is not on multimeters, but Brymen's is. For them it is make it or break it. For UEI, it is another department.

IIRC, shortly before the release of the 121GW UEI had discontinued their entire range of DMMs. Nowadays I see four models (https://www.ueitest.com/Ecommerce/category/products/multimeters), all 4000/6000 counts clearly for industrial markets.
I had tried to buy a few new UEI meters once Dave announced they were going to produce his meter.  They were already out of the business by that time which is why you never saw me run one. 
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 17, 2021, 01:24:05 am
Here is a photo with the battery holder removed.  Are the pins shown for flashing firmware??

Roger

I was guessing that connector allowed them to perform the alignment semi-automatically.  There appears to be two other unpopulated connectors which I was guessing were for development and not needed once they got into production.   During my evaluation, any changes the to firmware required that I change ICs.   

I have been told that "Firmware update will need Custom-made Programmer."
And I think way back they inidcated it was a re-programmable part as opposed to previous models that use OTP processors.

As for firmware changes, the BM235 had several firmware changes over 3-4 years as users slowly found obscure issues.
Just look at the ohm ranging issue with the BM867 recently, a once previously solidly tested meter.
So I'd be surprised if we don't see some firmware changes over the next few years.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 17, 2021, 01:27:58 am
While Dave's UEI meter still has some firmware problems noted with the prototype back in 2017,  the Brymen BM786 even though it's a brand new product, is much more mature (not to mention the quality of the parts and design).   The UEI meter needed that crutch.  I don't see that being the case with most high quality meters. 
UEI's core business is not on multimeters, but Brymen's is. For them it is make it or break it. For UEI, it is another department.

IIRC, shortly before the release of the 121GW UEI had discontinued their entire range of DMMs. Nowadays I see four models (https://www.ueitest.com/Ecommerce/category/products/multimeters), all 4000/6000 counts clearly for industrial markets.
I had tried to buy a few new UEI meters once Dave announced they were going to produce his meter.  They were already out of the business by that time which is why you never saw me run one.

Actually not true. They have been selling into the Chinese market under the Kane brand.
http://www.kanetest.com.cn/category.php?id=33 (http://www.kanetest.com.cn/category.php?id=33)
And there is a new model coming our in that 500 series, it's an upgraded design based on the 121GW design, but new much bigger case for a tripple display much like the original concep 121GW proposed right at the start, and I believe new firmware.
I have partly shown this in a previous video, it's probably not far from release.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 17, 2021, 03:13:52 am
Here is a photo with the battery holder removed.  Are the pins shown for flashing firmware??

Roger

I was guessing that connector allowed them to perform the alignment semi-automatically.  There appears to be two other unpopulated connectors which I was guessing were for development and not needed once they got into production.   During my evaluation, any changes the to firmware required that I change ICs.   

I have been told that "Firmware update will need Custom-made Programmer."
And I think way back they inidcated it was a re-programmable part as opposed to previous models that use OTP processors.

As for firmware changes, the BM235 had several firmware changes over 3-4 years as users slowly found obscure issues.
Just look at the ohm ranging issue with the BM867 recently, a once previously solidly tested meter.
So I'd be surprised if we don't see some firmware changes over the next few years.

Interesting about the programmer.  I have not looked into it beyond what I posted today. 

I bought the BM235 late and missed out on all the fun Scott was having with it finding early problems.  Outside of the cut away area around the connector for added clearance, the one I have seems fine for the most part.  I mentioned the autorange problem with it.   The BM869s has a similar problem but it's not anything that has hindered me. 

I've up'ed my game since looking at the very first handheld, even since looking at the BM235.   The benefit to the BM786 is that we find more problems early on and we have a company who not only wants to correct them but is also capable of doing so. 

After experiencing the 121GW, I have adopted the old adage of fool me once ....   I don't care if it's sold under UEI, Kane or Finest. 
Title: Re: New EEVblog BM786 Multimeter
Post by: ian.ameline on January 17, 2021, 09:25:41 pm
Are the calibration procedures documented for this meter?
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 17, 2021, 10:58:34 pm
Are the calibration procedures documented for this meter?
I assume you are asking about how to align the meter.   I'm sure Brymen has these procedures documented along with everything else about the design.   It's not available to the general public that I am aware of.
Title: Re: New EEVblog BM786 Multimeter
Post by: Andrew McNamara on January 17, 2021, 11:21:05 pm
Dave - the soft case seems to have disappeared from the store - are we going to see that return (particularly one suited to the larger BM786)?
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 18, 2021, 09:20:55 pm
Are the calibration procedures documented for this meter?

No they aren't.
They usually only release this to trusted major dealers.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 18, 2021, 09:21:44 pm
Dave - the soft case seems to have disappeared from the store - are we going to see that return (particularly one suited to the larger BM786)?

I don't particually want to carry multiple cases, so I might look into if it's possible to get one that suits all meters.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 20, 2021, 12:38:35 am
If you are wondering why your new BM786 multimeter didn't come with batteries, it's because DHL Express took it upon themselves to open every package and remove them & send them back. Alkaline batteries. Freak'n ALKALINE BATTERIES.

(https://pbs.twimg.com/media/EsIqOZcVkAAiZYx?format=jpg&name=900x900)
Title: Re: New EEVblog BM786 Multimeter
Post by: Kean on January 20, 2021, 12:39:50 am
If you are wondering why your new BM786 multimeter didn't come with batteries, it's because DHL Express took it upon themselves to open every package and remove them & send them back. Alkaline batteries. Freak'n ALKALINE BATTERIES.

WOW!  |O
Title: Re: New EEVblog BM786 Multimeter
Post by: tautech on January 20, 2021, 12:40:37 am
Muppets !  :palm:
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on January 20, 2021, 12:42:49 am
 |O :palm:
Title: Re: New EEVblog BM786 Multimeter
Post by: Ed.Kloonk on January 20, 2021, 12:44:48 am
-sigh-
Title: Re: New EEVblog BM786 Multimeter
Post by: wolfy007 on January 20, 2021, 01:19:18 am
Did they say why they removed alkaline batteries??? Or did the guy at the Xray machine just figure they should have them removed after spotting batteries...
Title: Re: New EEVblog BM786 Multimeter
Post by: ve7xen on January 20, 2021, 01:42:43 am
DHL's policy appears to prohibit the international shipping of Alkaline batteries, in all cases. The document is US-based, but presumably the International provisions apply network-wide. See page 7.

https://www.dhl.com/content/dam/dhl/local/us/dhl-ecommerce/documents/pdf/us-ecommerce-battery-shipping-policy.pdf (https://www.dhl.com/content/dam/dhl/local/us/dhl-ecommerce/documents/pdf/us-ecommerce-battery-shipping-policy.pdf)
Title: Re: New EEVblog BM786 Multimeter
Post by: Kleinstein on January 20, 2021, 09:21:24 am
For international shipping it makes sense to not include standard batteries. They only add to the weight and there is a small risk of the batteries to cause trouble: An unintentional short in a smashed parcel may start a fire - not very likely but alkaline cells often have quite some power. The other problem is leakage  :horse: - reduced air pressure in an aircraft can accelerate this.

Another point about not having batteries is that it makes it easier to spot a possible bomb from xray pictures.

There is no real need to have standard AA batteries shipped with the DMM. These are better bought locally in most places.
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on January 20, 2021, 10:52:37 am
So Dave - what are you going to do with a few kilos of alkaline batteries?
Title: Re: New EEVblog BM786 Multimeter
Post by: BU508A on January 20, 2021, 12:01:31 pm
So Dave - what are you going to do with a few kilos of alkaline batteries?

Leaking tests ...
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on January 20, 2021, 03:51:44 pm
At least they didn't reject the entire package i suppose. I received batteries with mine locally though
Title: Re: New EEVblog BM786 Multimeter
Post by: NoisyBoy on January 20, 2021, 08:09:09 pm
Saw it is back in stock, placed order for one.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 21, 2021, 12:46:11 am
At least they didn't reject the entire package i suppose. I received batteries with mine locally though

Looks like I'll have to rmeove the batteries for all international DHL shipments. Local will still have them.
Title: Re: New EEVblog BM786 Multimeter
Post by: symp on January 21, 2021, 09:27:45 am
Thanks for the decent energizers Dave, I shouldn't have to change them for a year or more if its as good on batteries as the 235
Title: Re: New EEVblog BM786 Multimeter
Post by: ian.ameline on January 21, 2021, 04:52:05 pm
The link to the manual here https://www.eevblog.com/files/BM789-Manual-Original-Final.pdf (https://www.eevblog.com/files/BM789-Manual-Original-Final.pdf) is broken...
Title: Re: New EEVblog BM786 Multimeter
Post by: drussell on January 21, 2021, 05:58:23 pm
The link to the manual here https://www.eevblog.com/files/BM789-Manual-Original-Final.pdf (https://www.eevblog.com/files/BM789-Manual-Original-Final.pdf) is broken...

Try this one:

https://www.eevblog.com/files/BM786-Manual-Original-Jan2021.pdf (https://www.eevblog.com/files/BM786-Manual-Original-Jan2021.pdf)
Title: Re: New EEVblog BM786 Multimeter
Post by: ian.ameline on January 21, 2021, 08:08:12 pm
Woo Hoo -- just arrived! (3 days to travel to the other side of the globe) It's a thing of beauty. Calibration out of the box is pretty damn good. Here is a recently calibrated 34401 (by Keysight at the end of November 2020) (warmed up for an hour along with the source. showing 5.00000V from a DMMCheck+. The EEVBlog Brymen is 1 count high. (it's been on for 30 minutes. It was 5 counts high for the first minute, then quickly settled at 5.0001V, and it hasn't budged since then.

 

Title: Re: New EEVblog BM786 Multimeter
Post by: ian.ameline on January 21, 2021, 08:34:03 pm
on DC milli-amps (@1.0mA), it is 2 counts higher than my 34401 . Resistance, 600ohm range (100ohms) it's 3 counts higher, and the 6k, 60k and 600k ranges (using 1K, 10K, and 100K resistors), the EEVBlog meter is within 1 count of the calibrated 34401.

For AC volts (5V AC, square wave @ 100hz), it is 24 counts lower than my 34401.

Pretty much spot on -- I don't think it could be any closer.

I'm very happy with my purchase.

Title: Re: New EEVblog BM786 Multimeter
Post by: ian.ameline on January 21, 2021, 08:42:08 pm
The batteries were in the package (3 energizer aaa in a small ziplock bag) but not installed in the meter -- so I guess DHL didn't remove all of them...
Title: Re: New EEVblog BM786 Multimeter
Post by: hopski on January 21, 2021, 08:57:38 pm
Mine came with batteries too. maybe the battery checker was on his break
Title: Re: New EEVblog BM786 Multimeter
Post by: ian.ameline on January 21, 2021, 09:13:51 pm
This soothes my OCD :-) (dialed in a random number :-) )

Title: Re: New EEVblog BM786 Multimeter
Post by: ian.ameline on January 21, 2021, 09:38:27 pm
One very minor error in the manual -- on page 16, where it depicts a north-american style outlet -- it has the neutral and live sides reversed. If the ground min is on the botom, the live side is on the right (and is slightly shorter than the neutral that is to the left). In that diagram on that page, the manual shows the live side is on the left.

Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 21, 2021, 10:24:46 pm
The batteries were in the package (3 energizer aaa in a small ziplock bag) but not installed in the meter -- so I guess DHL didn't remove all of them...

No, I shipped a lot more than they sent batteries back for. Maybe it was a sorted batch for one country and some dilligent handler opened one.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 22, 2021, 02:09:59 am
I just checked the signals on the internal header (not the one in the battery compartment) on the latest firmware model and still don't get any signals  :(
Was hoping they would have enabled support for the internal bluetooth module.
There is a chance it requires a pull up or something to activate it on bootup, but not likely.
Title: Re: New EEVblog BM786 Multimeter
Post by: dougg on January 22, 2021, 02:24:28 am
After having a 4 week, 10 phone call experience with DHL Express *** I was worried when the EEVBlog shop told me on Monday that the same courier company had my 768. It arrived today in Toronto, Canada so that I now have 4.5 multimeters. The 0.5 is a Metex M-3650 (from Dick Smiths ?) whose AC ranges are shot; it sits behind the TV and is used to determine the health of AA and AAA batteries. Went looking for that elusive 768 user manual and came up with this url: http://www.brymen.com/images/ProductsList/BM780_List/BM789-5-manual-print1-r7.pdf (http://www.brymen.com/images/ProductsList/BM780_List/BM789-5-manual-print1-r7.pdf) . It has the same snafu describing a north American outlet on page 18. Dave should fix the dead url at the start of this thread.
The 768 probes feel really good and the screw-on banana plug fittings are really useful. Did some measurements with a REF-101 from www.syscompdesign.com (http://www.syscompdesign.com) at 250 mV on 3 meters: Fluke 233, 121GW and the BM768: 249.7, 249.79 and 249.82 . Then set a SDG 2042X to the same voltage and got 251.3, 251.45 and 251.43 . A pretty good result IMO. The BM768 looks larger than the 121GW but the latter is higher and weighs about 80 grams more.

*** Jakarta -> Toronto, original package "EMS International". POS Indonesia handed it off to DHL who put it inside their packet and dropped a digit off my street number. DHL say they are innocent, IMO they are culpable, they should have put their label on the other side of the _original_ package.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 22, 2021, 03:01:49 am
I just checked the signals on the internal header (not the one in the battery compartment) on the latest firmware model and still don't get any signals  :(
Was hoping they would have enabled support for the internal bluetooth module.
There is a chance it requires a pull up or something to activate it on bootup, but not likely.

Yeah, I had tried that as well with the same results.
https://www.eevblog.com/forum/testgear/new-eevblog-bm786-multimeter/msg3417392/#msg3417392 (https://www.eevblog.com/forum/testgear/new-eevblog-bm786-multimeter/msg3417392/#msg3417392)
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 22, 2021, 07:49:33 am
Just a quick check, the unpopulated 4-pin connector with the two pairs of common pins is on the back side of U20 and ground, used to power the meter during development or provide power to some peripheral. 

The other unpopulated connector is not in parallel with the one you asked about.   It's possible that these two unpopulated connectors were both intended to control an add-on peripheral rather than development.  The LCD is far enough away that there is certainly room to add something but with the lack of mounting holes in this area, my guess is they are both for development.   Probing the two connectors,  I didn't see anything while trying different modes.

Missed this post.
I do believe this is for the optional bluetooth module.
Brymen said way back
Quote
We plan to just put Bluetooth capability on the PCB but leave it off for BM78x first generation models. Once we complete the software development, we will launch out BM78x with Bluetooth version models.
I asked then if it was possibble to at least make the processor output serial data or whatever so that users could retrofit their own module if needed. That would make it cool feature "hack". But it seems they didn't do it.
They memtioned a CYPRESS CYBLE-212006-01 module, but that pinout doesn't match, maybe a daughterboard?
Title: Re: New EEVblog BM786 Multimeter
Post by: drussell on January 22, 2021, 01:31:34 pm
Speaking of cool feature hacks....

I almost pulled the trigger and ordered one of these when Dave first released them as it looks like it would make a great "daily driver" replacement for my well-worn, aging Amrel (American Reliance) model 37 I've been using for the past 30 years...   ???  The good ol' 37 has served me well over the years (it is basically a functional clone of a Fluke 87, which was way out of my price range back in those days, sold for less than half the price, even has a yellow holster  8) ) but it is getting temperamental as a daily-use meter being carted around, left in vehicles in temperature extremes, etc.  I have to clean the zebra strip for the LCD and the button pads etc. every few months to keep it properly operational.  It's simply just wearing out from 30 years of constant use.

After watching Joe's video series, it looks pretty much perfect for me except for one aspect of one feature that I do use on a fairly regular basis, and that is being able to measure audio-frequency AC voltages to within a few percent, right up to at least 20 kHz.  Joe's testing indicates that the -3 dB point is way down at 7-8 kHz, which would be really annoying to have to attempt correct for or carry another meter all the time for making AF measurements.

Joe, since you've at least taken a cursory glance at the circuitry, is it likely that I could modify one to extend the frequency range slightly?  Do you suppose that the limit is coming from something in hardware, like where I could possibly just change a couple capacitors in a filter or something and get it up to at least 20-25 kHz for the -3 dB point, (ideally it would be nicer to have the -3 dB point up at 40-50 kHz but I could live with 20,) or is it something integrated into the chipset that is causing the limitation?  Like, how is it doing the RMS, is it being calclated in the main chip?  Not being able to field-update the firmware makes that a show-stopper if it's in the chip I suppose.

I have a tube of decent quality RMS converters somewhere (Analog Devices, I think) that I could make an adapter box or something with better response, but then guaranteed I won't have it with me when I need it, and it is not really practical to try to replace the whole AC front end unless it is already using a separate converter chip and that's where the limitation lies, which I highly doubt....

Anyway, any thoughts on whether I might be able to extend the AC frequency response about an octave and a half?

... that would turn it into pretty much the ideal meter for me!
Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on January 22, 2021, 01:47:15 pm
Anyway, any thoughts on whether I might be able to extend the AC frequency response about an octave and a half?

You could move to the next model in the line: BM789
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 22, 2021, 02:04:14 pm
After watching Joe's video series, it looks pretty much perfect for me except for one aspect of one feature that I do use on a fairly regular basis, and that is being able to measure audio-frequency AC voltages to within a few percent, right up to at least 20 kHz.  Joe's testing indicates that the -3 dB point is way down at 7-8 kHz, which would be really annoying to have to attempt correct for or carry another meter all the time for making AF measurements.

The BM789 does that.
I don't have a BM789 to compare, but it's the same PCB.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on January 22, 2021, 02:05:35 pm
After watching Joe's video series, it looks pretty much perfect for me except for one aspect of one feature that I do use on a fairly regular basis, and that is being able to measure audio-frequency AC voltages to within a few percent, right up to at least 20 kHz.  Joe's testing indicates that the -3 dB point is way down at 7-8 kHz, which would be really annoying to have to attempt correct for or carry another meter all the time for making AF measurements.

Anyway, any thoughts on whether I might be able to extend the AC frequency response about an octave and a half?

... that would turn it into pretty much the ideal meter for me!

Brymen makes plenty of meters simliar to this one. A lot of them go up to 100kHz.

Title: Re: New EEVblog BM786 Multimeter
Post by: drussell on January 22, 2021, 02:12:35 pm
Anyway, any thoughts on whether I might be able to extend the AC frequency response about an octave and a half?

You could move to the next model in the line: BM789

Well, obviously...  but then I wouldn't be buying the EEVblog version from Dave.  :)

The BM789 also doesn't appear to be very widely available yet and most places also appear to want way more money than Dave is charging for his BM786.
Title: Re: New EEVblog BM786 Multimeter
Post by: drussell on January 22, 2021, 02:15:03 pm
After watching Joe's video series, it looks pretty much perfect for me except for one aspect of one feature that I do use on a fairly regular basis, and that is being able to measure audio-frequency AC voltages to within a few percent, right up to at least 20 kHz.  Joe's testing indicates that the -3 dB point is way down at 7-8 kHz, which would be really annoying to have to attempt correct for or carry another meter all the time for making AF measurements.

The BM789 does that.
I don't have a BM789 to compare, but it's the same PCB.

Yeah, I know...  That's why I was wondering if it is a component-stuffing difference or a firmware difference.

I don't really need any of the "other" features on the 789, hence my question.  :)
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 22, 2021, 02:16:33 pm
That's why I was wondering if it is a component-stuffing difference or a firmware difference.

Brymen provided me with a 789 as well which I plan to run soon.   It has the latest firmware installed but may no longer be in calibration.  The firmware is different for the 786 and 789.   

I'll ask them about the BT interface.  It would be nice to connect one of these up with LabView. 
Title: Re: New EEVblog BM786 Multimeter
Post by: drussell on January 22, 2021, 02:26:35 pm
Brymen provided me with a 789 as well which I plan to run soon.   It has the latest firmware installed but may no longer be in calibration.  The firmware is different for the 786 and 789.   

Ah, you have a 789 also...  Sweet!

Obviously the 786 and 789 will have different firmware since the 789 supports the LowZ AutoV, dBm, has T2, etc. I'm just curious if the one spec difference of the ACV frequency is an intentional firmware limitation or if it is related to actual filter components on the PCB, thats all.  My suspicion is that it is most likely a software limitation.

I would just like to know if you happen to notice any differences in the actual circuitry, thanks!   :)
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 22, 2021, 03:15:09 pm
Brymen provided me with a 789 as well which I plan to run soon.   It has the latest firmware installed but may no longer be in calibration.  The firmware is different for the 786 and 789.   

Ah, you have a 789 also...  Sweet!

Obviously the 786 and 789 will have different firmware since the 789 supports the LowZ AutoV, dBm, has T2, etc. I'm just curious if the one spec difference of the ACV frequency is an intentional firmware limitation or if it is related to actual filter components on the PCB, thats all.  My suspicion is that it is most likely a software limitation.

I would just like to know if you happen to notice any differences in the actual circuitry, thanks!   :)

I have no idea what the hardware/firmware differences are.  If you need a feature not available on the 786, I suggest just buying one that meets your needs rather than attempting to modify it.   I use that 2 X K-type feature on the BM869s a fair amount.   It's one of the reasons I bought it.  The UNI-T UT181A also supports it. 
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 22, 2021, 09:58:21 pm
Obviously the 786 and 789 will have different firmware since the 789 supports the LowZ AutoV, dBm, has T2, etc. I'm just curious if the one spec difference of the ACV frequency is an intentional firmware limitation or if it is related to actual filter components on the PCB, thats all.  My suspicion is that it is most likely a software limitation.

If they are smart then the firmware will be indentical, and only a single fuse bit determines what features it has.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 23, 2021, 02:58:54 am
Obviously the 786 and 789 will have different firmware since the 789 supports the LowZ AutoV, dBm, has T2, etc. I'm just curious if the one spec difference of the ACV frequency is an intentional firmware limitation or if it is related to actual filter components on the PCB, thats all.  My suspicion is that it is most likely a software limitation.

If they are smart then the firmware will be indentical, and only a single fuse bit determines what features it has.

What do you feel makes this the smart thing to do?  Makes it easier to maintain the code base?   Like the idea of promoting upgrades for beginners with a soldering iron?   Sell more meters?   
Title: Re: New EEVblog BM786 Multimeter
Post by: Monkeh on January 23, 2021, 03:04:51 am
Obviously the 786 and 789 will have different firmware since the 789 supports the LowZ AutoV, dBm, has T2, etc. I'm just curious if the one spec difference of the ACV frequency is an intentional firmware limitation or if it is related to actual filter components on the PCB, thats all.  My suspicion is that it is most likely a software limitation.

If they are smart then the firmware will be indentical, and only a single fuse bit determines what features it has.

What do you feel makes this the smart thing to do?  Makes it easier to maintain the code base?   Like the idea of promoting upgrades for beginners with a soldering iron?   Sell more meters?

Fuse bit would be internal to the chip, not something you can solder. Potentially means you can flash the firmware image on a device, not set the fuse bits, perform a full test and calibration, and then later down the chain determine which model it is - less stock to keep of the boards, easier for replacements under warranty, and so forth. Less chance of strange and obscure bugs from different firmware builds, no 'oops we can't fit the image for this model in but all the others are fine', no need to build and ship multiple firmware images when you update it, which removes a potential human error leaving an old build in place..

Sorry, sort of a wall-o-thoughts there, but in general one image to rule them all removes a lot of problems.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 23, 2021, 03:41:38 am
Quote
less stock to keep of the boards,
Could you please explain this?
Title: Re: New EEVblog BM786 Multimeter
Post by: Monkeh on January 23, 2021, 03:59:38 am
Quote
less stock to keep of the boards,
Could you please explain this?

If you only have one board design with one set of components and one firmware image, you may not need to keep as many assembled and tested on hand for warranty replacement, for example. Yes, it sort of mushes in with a second point from my post. I don't know that the boards are identical between versions of this meter (quite possibly not, honestly), but ticking both boxes potentially leaves you with more flexible stock. Same idea as using one case moulding with just different print on it, in some products that would be just a label stuck on covering unused button holes and so forth.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 23, 2021, 04:19:58 am
Bare boards are the same but once populated they are different sub assemblies.  The hardware and firmware are unique.  Even at final assembly, we have a case using custom colors.  I doubt there's much concern about it.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 23, 2021, 05:26:13 am
Obviously the 786 and 789 will have different firmware since the 789 supports the LowZ AutoV, dBm, has T2, etc. I'm just curious if the one spec difference of the ACV frequency is an intentional firmware limitation or if it is related to actual filter components on the PCB, thats all.  My suspicion is that it is most likely a software limitation.
If they are smart then the firmware will be indentical, and only a single fuse bit determines what features it has.
What do you feel makes this the smart thing to do?  Makes it easier to maintain the code base?   Like the idea of promoting upgrades for beginners with a soldering iron?   Sell more meters?

Obviously from a code point of view it's highly preferable to have a single code base for all 3 meters in the series. So when you fix a bug or change/add a feature in one it gets fixed in all the others.
The code just reads a single flag like "if 786 or 789 then do this" etc.
You'd have to be crazy to want to maintain and compile three entirely different code bases for effectively the same meter. The model bit just gets set in the programmer software in a non-volatile register somewhere and the code reads that as required and either ignores or does that function that models has.
Title: Re: New EEVblog BM786 Multimeter
Post by: Kleinstein on January 23, 2021, 12:49:10 pm
One can have a common code base with a check in the actual meter, or one can do the different versions at compile time, e.g. with a constant to change between versions - this would need less momory in the meter (or at least be lowest range one).

I would not expect the AC frequency limit to be a software point. AFAIK they use hardware RMS chips, so there is not much to adjust in software. The difference would be more a thing of the used amplifer and RMS converter grade, maybe filter caps. Even for the numerical RMS way that some chip sets more support, there is usually no provision for extra filtering, other than maybe choose the sampling rate. It could be a nice feature to have a choosable BW for RMS. Higher BW also means more noise / background.  After all his is a DMM and not a spectrum analyser - so don't expect too much.
Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on January 23, 2021, 01:58:13 pm
If the controller is programmed in-circuit, there is no problem with separate firmware builds for the different models, but they could still use the same code base.
If the controller is programmed before mounting it on the PCB, it would be easier to use a common code for all models and then use a bit in the calibration memory or a link on the circuit board to select the actual model.

The 100kHz bandwidth requires compensation capacitors for the input stage, the 7kHz probably not.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on January 23, 2021, 03:14:33 pm
Next to the LCD controller, there is an empty footprint for an IC and its components..
By the looks of it, it might be AD8436 True RMS converter chip. Some of the multimeter chips have built in low bandwidth RMS converters, for low cost options, with option to add external higher performance RMS converter for better specced meters.
Here we might have the same situation..
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on January 23, 2021, 04:49:38 pm
Obviously the 786 and 789 will have different firmware since the 789 supports the LowZ AutoV, dBm, has T2, etc. I'm just curious if the one spec difference of the ACV frequency is an intentional firmware limitation or if it is related to actual filter components on the PCB, thats all.  My suspicion is that it is most likely a software limitation.
If they are smart then the firmware will be indentical, and only a single fuse bit determines what features it has.
What do you feel makes this the smart thing to do?  Makes it easier to maintain the code base?   Like the idea of promoting upgrades for beginners with a soldering iron?   Sell more meters?

Obviously from a code point of view it's highly preferable to have a single code base for all 3 meters in the series. So when you fix a bug or change/add a feature in one it gets fixed in all the others.
The code just reads a single flag like "if 786 or 789 then do this" etc.
You'd have to be crazy to want to maintain and compile three entirely different code bases for effectively the same meter. The model bit just gets set in the programmer software in a non-volatile register somewhere and the code reads that as required and either ignores or does that function that models has.
I agree about using a common code base and conditional builds.  Of course, if it's the identical firmware there's no need for that. 

I never asked them why they spun up different firmware.  To me, it doesn't matter as long as they are able to maintain it.  Based on how well they kept up with me, I don't see that as a problem.   UEI had one meter to maintain and couldn't pull it off.   I think there's a difference in the skill level of the developers which may be a much bigger factor. 

Next to the LCD controller, there is an empty footprint for an IC and its components..
By the looks of it, it might be AD8436 True RMS converter chip. Some of the multimeter chips have built in low bandwidth RMS converters, for low cost options, with option to add external higher performance RMS converter for better specced meters.
Here we might have the same situation..

I didn't spend any time trying to sort out the differences beyond changing the IC.   While apart, I noticed the additional shield and trimmers.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on January 24, 2021, 09:30:29 am
Next to the LCD controller, there is an empty footprint for an IC and its components..
By the looks of it, it might be AD8436 True RMS converter chip. Some of the multimeter chips have built in low bandwidth RMS converters, for low cost options, with option to add external higher performance RMS converter for better specced meters.
Here we might have the same situation..

Yes, that was what I thought when I first saw it, but have not checked as I don't have a 789.
Title: Re: New EEVblog BM786 Multimeter
Post by: NoisyBoy on January 30, 2021, 08:19:06 am
Hey Dave,

Thank you so much for getting the meter out, it arrived in the US in 3 days. 

Interestingly, the three AAA batteries arrived with the meter, so no issue with DHL. They also improve the delivery date by 3 days, a pleasant surprise as we are expecting another snowstorm this weekend.

Did some quick measurements against my EDC 522 reference, as well as against my other bench meters with current calibrations, the meter is very accurate, even in the worst case, it is only 1-2 counts off.  First Brymen I own, it is definitely a keeper when I need mobility.  Its accuracy is as good as the handheld Flukes I own, and with higher precision. 

It is a great buy for its price point, not to mention showing support for a community of nice people I enjoy. 
Title: Re: New EEVblog BM786 Multimeter
Post by: jknightandkarr on January 30, 2021, 09:50:19 am
Dave,
     I just got my BM235 from Amazon and my BM786  just 24 hours apart. Gotta say that I love them both!  The features they both have are really nice and I esp. love the idea that I can't mess it up if I plug the probes into the wrong sockets.  VERY VERY nice idea!  Being in school at DeVry University and for my hobby work, these will come in VERY handy!   :-+ :-+ :-+ :-+

Joe 
Title: Re: New EEVblog BM786 Multimeter
Post by: Shannon on January 30, 2021, 03:35:38 pm
I love this no bull shit package!

Every engineer has to spent half of the work time to naming the schametic net or value in code!

Less is more.
Title: Re: New EEVblog BM786 Multimeter
Post by: bc888 on February 08, 2021, 08:51:18 pm


2 things...I have a rag tag collection of things that measure Non-Contact Voltage but this BM786 is the best. Hands down. Better than anything I've ever used. Finally! no more sawing through hidden live power wires behind the walls:-)

2nd) Continuity beep is not the fastest. Wish it was.

3rd) They did not cheap out on the leads. Good stuff.

Thanks Dave!!!!
Title: Re: New EEVblog BM786 Multimeter
Post by: bc888 on February 08, 2021, 08:57:34 pm
BTW, can anyone direct me where is the BM786 manual download? It's not here now, https://www.eevblog.com/files/BM789-Manual-Original-Final.pdf (https://www.eevblog.com/files/BM789-Manual-Original-Final.pdf), and I didn't find it via Eevblog Wiki or search. Didn't find it on Brymens site either:

Nevermind, rooted around and got it here: https://www.eevblog.com/files/BM786-Manual-Original-Jan2021.pdf (https://www.eevblog.com/files/BM786-Manual-Original-Jan2021.pdf)
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on February 09, 2021, 07:14:07 am
The continuity beep is very responsive on mine i haven't noticed any lag/latching problems at all, i am using different leads with mine maybe its that.
NCV is incredibly sensitive on this meter i was able to detect live wiring in the wall quite easily
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on February 09, 2021, 09:37:14 am
" Continuity beep is not the fastest. Wish it was."
You are probably referring to the Beeplit Diode test, Beeplit Continuity function is the one on the Ohms range which is instantaenous
Title: Re: New EEVblog BM786 Multimeter
Post by: Frank987 on February 14, 2021, 10:39:01 am
There is a problem with the 400 mA Fuse: The BM786 manual  says a SIBA Fuse 7017240;0.4A/1000V is used for the 600 mA range.  In the SIBA datasheet https://download.siba.de/pdf/artikel/SIBA-GSS-7017240.pdf you find that the 400 mA fuse blows typical after 0.1 s at 1,5 * 400 mA  = 600 mA. The I²t value of the fuse is 0.07 A²s, giving about 0.2 s at 600 mA. So something must be wrong as it s not possible to do measurements in less than 0.2 s. Either the manual is wrong or the 600 mA current rating of the meter or the meter is supplied with the wrong fuse, should be SIBA 7017240.0,63 with 630 mA.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on February 14, 2021, 11:18:29 am
There is a problem with the 400 mA Fuse: The BM786 manual  says a SIBA Fuse 7017240;0.4A/1000V is used for the 600 mA range.  In the SIBA datasheet https://download.siba.de/pdf/artikel/SIBA-GSS-7017240.pdf you find that the 400 mA fuse blows typical after 0.1 s at 1,5 * 400 mA  = 600 mA. The I²t value of the fuse is 0.07 A²s, giving about 0.2 s at 600 mA. So something must be wrong as it s not possible to do measurements in less than 0.2 s. Either the manual is wrong or the 600 mA current rating of the meter or the meter is supplied with the wrong fuse, should be SIBA 7017240.0,63 with 630 mA.

If you look at that diagram, that dotted line on the left is not the fuse curve.  Fuse reaction curves are those two short ones on the right (marked with white and black triangles).
Fuse will blow in 60 msec at 4X of nominal current. At 2,75xIn (nominal current) it will not even blow...
Regards,
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on February 14, 2021, 12:56:46 pm
If you look at that diagram, that dotted line on the left is not the fuse curve.

What's the line on the left for?
Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on February 14, 2021, 01:16:39 pm
If you look at that diagram, that dotted line on the left is not the fuse curve.

What's the line on the left for?

I would expect it was minimum and maximum, i.e. the fuse may or may not blow in between the two curves. This also matches the table where 2.75x do not contain any values.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on February 14, 2021, 02:05:39 pm
If you look at that diagram, that dotted line on the left is not the fuse curve.

What's the line on the left for?
I wouldn't know, not my diagram. I presume that is some Joule heat (current/time integral) limit...
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on February 14, 2021, 02:07:09 pm
Maybe it's guaranteed not to blow to the left of that line.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on February 14, 2021, 02:24:35 pm
No. That's the minimum line for the 1A/2A fuse. 1ms to 1 hr. (4 In to 1 In).
Title: Re: New EEVblog BM786 Multimeter
Post by: Frank987 on February 14, 2021, 04:37:33 pm
Now I have read the SIBA homepage. I agree, the left curve is the minimum time not the typical time for the fuse to break and curve is only valid for 1A  1.6A and 2A fuses. Better calculation is with the "SchmelzintegralI" I²ts Value, which is 0.07 A²s for the 400 mA fuse. Now with 0.6 Amp the time to break is 0.07 / 0.6² = 0.194 s. I can not read the Multimeter in this short time as it does only 5 measurements / s. So before 1 measurement is done the fuse is broken...
Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on February 14, 2021, 04:56:07 pm
Better calculation is with the "SchmelzintegralI" I²ts Value, which is 0.07 A²s for the 400 mA fuse. Now with 0.6 Amp the time to break is 0.07 / 0.6² = 0.194 s. I can not read the Multimeter in this short time as it does only 5 measurements / s. So before 1 measurement is done the fuse is broken...

It sounds like the integral specified the minium time, i.e. the fuse will at least last 0.2second, but may never blow at all.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on February 14, 2021, 05:02:43 pm
t is the time for the fuse to completely open with overcurrent.
600 mA equals 150% of In and the FF fuse must not open for an hour, by IEC regulations 60127.
UL 248 standards are different:
4 hours at 110% and 60 minutes max at 135%.

A fuse made to UL/CSA/ANCE 248-14 and operated at its rated current will
eventually open. For this reason UL fuses are customarily operated
at no more than 75 percent of their rated current.

Currents between 110 and 135 percent of fuse ratings present a
severe challenge to the designer because they can subject parts to
high heat for extended periods of time, and because fuse behavior
at these currents can be difficult to predict.
  Littelfuse
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 15, 2021, 12:56:24 pm
There is a problem with the 400 mA Fuse: The BM786 manual  says a SIBA Fuse 7017240;0.4A/1000V is used for the 600 mA range.  In the SIBA datasheet https://download.siba.de/pdf/artikel/SIBA-GSS-7017240.pdf you find that the 400 mA fuse blows typical after 0.1 s at 1,5 * 400 mA  = 600 mA. The I²t value of the fuse is 0.07 A²s, giving about 0.2 s at 600 mA. So something must be wrong as it s not possible to do measurements in less than 0.2 s. Either the manual is wrong or the 600 mA current rating of the meter or the meter is supplied with the wrong fuse, should be SIBA 7017240.0,63 with 630 mA.

The BM235 uses the same 400mA fuse for its 600mA range and it's never been an issue.
I asked Brymen years ago if a 500mA fuse could be used on the BM235 and their response was

Quote
Not recommended.
For measuring 600mA in short period, there is no problem to use that fuse. But for measuring 600mA continuously, it will heat and the internal ambient temperature around that fuse may reach to the one out of plastic case temperature spec.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on February 17, 2021, 05:48:41 am
It seems to me that Brymen is obfuscating here.
A SIBA 630mA fuse will only heat up by a few degrees when subjected to 600mA, whereas the 400mA fuse, at 150% of its current rating, could possibly melt plastics, before it opens one hour later.
The Bussmann 440mA fuse temperature only rises by 6 degrees above ambient (datasheet), when operating at its max rated current.
Title: Re: New EEVblog BM786 Multimeter
Post by: fabrizio_fabrice on February 21, 2021, 08:47:04 pm
Just discovered the 786 doesn't have an AC (only) voltage range!?  But it has the same symbols on the face as mV, mA, and µA — and they do cycle through all three.

I thought it was just an oversight in the manual, because I hadn't heard mention of this (I don't live here).  Now I read the manual in a different light— p. 7 heading is: DCV; DC+ACV.   No AC volts!   Measuring AC gain needs some math given the usual change in DC biases present.

What's the rationale?
Title: Re: New EEVblog BM786 Multimeter
Post by: Monkeh on February 21, 2021, 08:50:25 pm
Just discovered the 786 doesn't have an AC (only) voltage range!?  But it has the same symbols on the face as mV, mA, and µA — and they do cycle through all three.

I thought it was just an oversight in the manual, because I hadn't heard mention of this (I don't live here).  Now I read the manual in a different light— p. 7 heading is: DCV; DC+ACV.   No AC volts!   Measuring AC gain needs some math given the usual change in DC biases present.

What's the rationale?

The rationale is you rotate the switch one position counter-clockwise to the ACV position.
Title: Re: New EEVblog BM786 Multimeter
Post by: fabrizio_fabrice on February 21, 2021, 10:32:15 pm

What's the rationale?
The rationale is you rotate the switch one position counter-clockwise to the ACV position.
Ahhhh.... thanks, Monkeh!    I'm 'challenged' |O by manuals that cover multiple versions. 

It would make more sense to me if they integrated ACV with the DC and AC+DC? settings like the other parameters.  So much for HID protocol.
Title: Re: New EEVblog BM786 Multimeter
Post by: Monkeh on February 21, 2021, 10:34:58 pm

What's the rationale?
The rationale is you rotate the switch one position counter-clockwise to the ACV position.
Ahhhh.... thanks, Monkeh!    I'm 'challenged' |O by manuals that cover multiple versions. 

It would make more sense to me if they integrated ACV with the DC and AC+DC? settings like the other parameters.  So much for HID protocol.

Too many settings. ACV, ACV + LPF ('VFD mode'), DCV, DC+ACV, dBm. Better to have a couple more switch positions than have people cycle through so many modes by button. The mV range is less used so they just crammed them all in there, and it's a pain.
Title: Re: New EEVblog BM786 Multimeter
Post by: IanB on February 22, 2021, 12:39:19 am
It would make more sense to me if they integrated ACV with the DC and AC+DC? settings like the other parameters.  So much for HID protocol.

Sometimes turning the dial can mechanically switch certain components in or out of the circuit. If they tried to do it using push buttons they would have to use a relay instead. The rotary dial is more reliable.
Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on February 22, 2021, 05:55:22 am
When the rotary switch has a separate VAC position the reason is often that it switches a capacitor in series with the input. VDC and VDC+VAC must be on another position because they are done without capacitor.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 22, 2021, 07:30:34 am
It would make more sense to me if they integrated ACV with the DC and AC+DC? settings like the other parameters.  So much for HID protocol.

There are specifc reasons why there is a separate AC volt rage.
The BM235 meter for example (among other brands) that shares the AC & DC switch position has a limitation of what it can measure, and also hence auto-range in the presence of AC+DC signals.
The AC position also allows dedicated AC coupling.
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on February 23, 2021, 03:32:45 am
DON'T BUY THE BMH-02 MAGNETIC HANGER IT APPEARS TO HAVE PERMANENTLY DAMAGED THE BEEPER IN THE METER, THE BEEPER IS  INAUDIBLE WHILE THE MAGNETIC HANGER IS PRESENT & IS NOW ONLY HALF THE VOLUME IT SHOULD BE WHEN REMOVED
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 23, 2021, 09:13:16 am
Answering the fuse question turned into a main channel video:
https://www.youtube.com/watch?v=OVz9YPfMHuI (https://www.youtube.com/watch?v=OVz9YPfMHuI)
Title: Re: New EEVblog BM786 Multimeter
Post by: MK14 on February 23, 2021, 09:48:08 am
You might get complaints, as you are bordering on swearing, or worse, when the thing broke on you, unexpectedly.

https://youtu.be/OVz9YPfMHuI?t=277
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 23, 2021, 10:55:43 am
You might get complaints, as you are bordering on swearing, or worse, when the thing broke on you, unexpectedly.
https://youtu.be/OVz9YPfMHuI?t=277

The word bloody, are you serious?  :-//
Title: Re: New EEVblog BM786 Multimeter
Post by: BU508A on February 23, 2021, 11:00:37 am
Guess, he is bloody serious.  :-DD
Title: Re: New EEVblog BM786 Multimeter
Post by: MK14 on February 23, 2021, 11:00:43 am
You might get complaints, as you are bordering on swearing, or worse, when the thing broke on you, unexpectedly.
https://youtu.be/OVz9YPfMHuI?t=277

The word bloody, are you serious?  :-//

I suspect it is differences, between countries, cultures, how people have been brought up, etc.

I agree, it is 'BORDERLINE' swearing.

As the video was unlisted when I watched that part, with around 34 views, I thought it a good time to mention it. In case you changed your mind.

tl;dr
I was serious. But it is relatively MINOR, I agree.
Title: Re: New EEVblog BM786 Multimeter
Post by: MK14 on February 23, 2021, 11:06:00 am
I had a quick look (Google). It seems the Australians, have accepted it, and don't consider it swearing.

Source:
https://en.wikipedia.org/wiki/Bloody

Quote
Usage outside the UK
Bloody has always been a very common part of Australian speech and has not been considered profane there for some time. The word was dubbed "the Australian adjective" by The Bulletin on 18 August 1894. One Australian performer, Kevin Bloody Wilson, has even made it his middle name. Also in Australia, the word bloody is frequently used as a verbal hyphen, or infix, correctly called tmesis as in "fanbloodytastic".

EDIT:
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on February 23, 2021, 11:13:26 am
It seems the Australians, have accepted it, and don't consider it swearing.

In 99% of situations, it wouldn't even raise an eyebrow.
Title: Re: New EEVblog BM786 Multimeter
Post by: tautech on February 23, 2021, 11:27:45 am
It seems the Australians, have accepted it, and don't consider it swearing.

In 99% of situations, it wouldn't even raise an eyebrow.
:-DD
Except when described as bloody and are actually covered in it !
Those that prepare their own from paddock to plate think nothing of it.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 23, 2021, 11:41:37 am
  • I'm on the VERY HIGH sensitivity side, as regards stuff like this. So, DON'T worry too much about me complaining about it
  • Bloody H***, is the REALLY bad one. Although even that, is probably not considered too bad these days, I suspect

Bloody oath, too bloody right mate, you said it.
You wouldn't survive in Australia.
It's even in our official government tourism commercials!

https://www.youtube.com/watch?v=Y-ZLr9ePuj8 (https://www.youtube.com/watch?v=Y-ZLr9ePuj8)

Don't worry, I ignore everyone who complains about my speech as a matter of course. Well, actually, if anything it makes me want to do it more  ;D[/list]
Title: Re: New EEVblog BM786 Multimeter
Post by: MK14 on February 23, 2021, 11:50:14 am
Bloody oath, too bloody right mate, you said it.
You wouldn't survive in Australia.
Don't worry, I ignore everyone who complains about my speech as a matter of course. Well, actually, if anything it makes me want to do it more  ;D

There use to be on British Television, comedy programmes, (made by UK people, for UK people), making fun of how the British are, with things like swear words, and attitudes to other things.

At the end of the day, it is an 'Engineering' channel, for mainly engineers. So, it should be acceptable.
I'm not 100% sure, but I think some of the engineering channels, are considerably worse.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 23, 2021, 11:51:32 am
It seems the Australians, have accepted it, and don't consider it swearing.

In 99% of situations, it wouldn't even raise an eyebrow.

Only with the bloody poms, Canadians and Singaporeans.
https://en.wikipedia.org/wiki/So_where_the_bloody_hell_are_you%3F
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on February 23, 2021, 12:57:08 pm
Interesting video, but it still doesn't answer the question of why Brymen installed an underrated SIBA 400mA fuse instead of a more appropriate 630mA one, in their 600mA range multimeter?

The ASTM fuse is built to UL248 standard, which means it has to blow within one hour at 135% of nominal current.
The SIBA fuse has to comply with IEC 60127, which stipulates that it must not open for one hour at 150% of nominal current.
That should explain why the SIBA fuse lasts a lot longer at 600mA than the ASTM unit.

It is still a mystery as to how a SIBA fuse could comply with both standards at the same time.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 23, 2021, 01:04:49 pm
Someone wrote me about the magnetic strap having an effect on the beepers loudness.  I was able to replicate it on all the 78x meters I have.   It's not a small effect.  You can make the audio very faint with it.  Really odd.   I have written Brymen about it. 

I don't use these magnetic hangers often and wonder if there are other meters with a similar problem. 
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on February 23, 2021, 01:22:01 pm
You might get complaints, as you are bordering on swearing, or worse, when the thing broke on you, unexpectedly.
https://youtu.be/OVz9YPfMHuI?t=277

The word bloody, are you serious?  :-//

You said "bugger" as well!

Oh, now I've said it!  :scared:

At the end of the day, it is an 'Engineering' channel, for mainly engineers. So, it should be acceptable.

I'm not sure I follow that logic.

I'm not 100% sure, but I think some of the engineering channels, are considerably worse.

Big Clive lets the odd "F" word slip past his lips.

I know of another (british) toober who has a large selection of 'substitute' words, eg. "What the fudge is that?". Some of them are quite creative.

Weird how the substitutes aren't deemed offensive when the intention/intonation is exactly the same.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 23, 2021, 02:03:19 pm
Interesting video, but it still doesn't answer the question of why Brymen installed an underrated SIBA 400mA fuse instead of a more appropriate 630mA one, in their 600mA range multimeter?

Fluke and Keysight use a 440mA fuse on the 600mA range, better ask them too.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on February 23, 2021, 02:36:55 pm
Don't worry, I ignore everyone who complains about my speech as a matter of course. Well, actually, if anything it makes me want to do it more

Right, you're bloody well right
You know you got a right to say
Me I don't care anyway
  ;D

https://www.youtube.com/watch?v=-YAMbLHcS-8 (https://www.youtube.com/watch?v=-YAMbLHcS-8)

Interesting video, but it still doesn't answer the question of why Brymen installed an underrated SIBA 400mA fuse instead of a more appropriate 630mA one, in their 600mA range multimeter?
Fluke and Keysight use a 440mA fuse on the 600mA range, better ask them too.
Bussmann 44/100 starts the plot at 300s above 1A on their chart
https://datasheet.octopart.com/DMM-B-44/100-Cooper-Bussmann-datasheet-85426.pdf (https://datasheet.octopart.com/DMM-B-44/100-Cooper-Bussmann-datasheet-85426.pdf)
Title: Re: New EEVblog BM786 Multimeter
Post by: dcac on February 23, 2021, 03:15:35 pm
Interesting video, but it still doesn't answer the question of why Brymen installed an underrated SIBA 400mA fuse instead of a more appropriate 630mA one, in their 600mA range multimeter?

Fluke and Keysight use a 440mA fuse on the 600mA range, better ask them too.

Another thing to consider - how many cycles of (over)current can the fuse handle. Even if it didn’t blow on the first cycle - let it cool down and then try again.

To me if an Amp input is rated 600mA I would expect it to handle 600mA almost indefinitely and for a considerable amout of cycles. What'is the point of printing Max 0.6A on the meter if that doesn’t really tell you for how long or how many times it can handle that.

Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on February 23, 2021, 04:13:23 pm
Interesting video, but it still doesn't answer the question of why Brymen installed an underrated SIBA 400mA fuse instead of a more appropriate 630mA one, in their 600mA range multimeter?

Fluke and Keysight use a 440mA fuse on the 600mA range, better ask them too.

That's been addressed in an earlier post.
Bussmann doesn't make a 600mA fuse for multimeters and thus Fluke and Keysight limit their range to 400mA, with some allowance above for a stated limited time.

The Fluke 87 V has a a range of 400mA only, with a specified limit of 400mA continuous and overload 600mA for 18 hours.
The Fluke 179 has a range of 400mA only, with a specified limit of 600 mA overload for 2 minutes maximum, 10 minutes rest.

The Brymen 786 should have a limited mA range of 400mA, not 600mA, to avoid heat damage to the meter.

Keysight: Current can be measured at 440 mA continuously, and > 440 mA to 600 mA for 20 hours maximum.
To avoid blowing the multimeter’s 440 mA fuse, use the terminal only if you are sure the current is less than 440 mA.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 23, 2021, 06:30:57 pm
Enjoyed the video on the black art of fuses.   
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on February 23, 2021, 06:49:52 pm
It seems the Australians, have accepted it, and don't consider it swearing.

In 99% of situations, it wouldn't even raise an eyebrow.

Only with the bloody poms, Canadians and Singaporeans.
https://en.wikipedia.org/wiki/So_where_the_bloody_hell_are_you%3F

As far as we poms go, it's only really the knitted cardie brigade that gets upset by swearing these days.

I listen to a lot of BBC Radio 4 and it's quite common to hear much stronger language than that in the 6:30 pm comedy slot.

I guess MK14 hasn't heard Dave telling the camera to focus yet, that one always makes me chuckle... and he should definitely avoid AvE's channel. He's Canadian btw...



On topic, it would seem to make sense as Wytnucls suggests for Brymen to rate the meter for 400mA continuous and 600mA peak.
Title: Re: New EEVblog BM786 Multimeter
Post by: Algoma on February 23, 2021, 07:02:19 pm
BM786 Arrived today, bit of a quirk on the Ohms Auto Range and Diode Check.. Flickers around kohms and Mohms then settles on 1Mohms with or without leads attached, after a while finally goes to OL after quite a while. Low Ohms (Continuity check, and Diode check both beep randomly).
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 23, 2021, 07:06:11 pm
BM786 Arrived today, bit of a quirk on the Ohms Auto Range and Diode Check.. Flickers around kohms and Mohms then settles on 1Mohms with or without leads attached, after a while finally goes to OL after quite a while. Low Ohms (Continuity check, and Diode check both beep randomly).

That doesn't seem right.  I wonder what "quite a while" means.
Title: Re: New EEVblog BM786 Multimeter
Post by: Wytnucls on February 23, 2021, 07:16:12 pm
Merriam Webster:
Definition of quite a while
: a long time  >:D
Title: Re: New EEVblog BM786 Multimeter
Post by: Algoma on February 23, 2021, 07:16:41 pm
That doesn't seem right.  I wonder what "quite a while" means.

Its intermittent and inconsistent.. 5 seconds to 30 seconds. Diode test mode intermittently flashes low Forward Voltage values, indicating like a shorted diode, even with no leads attached.
Title: Re: New EEVblog BM786 Multimeter
Post by: MK14 on February 23, 2021, 07:17:52 pm
As far as we poms go, it's only really the knitted cardie brigade that gets upset by swearing these days.

I listen to a lot of BBC Radio 4 and it's quite common to hear much stronger language than that in the 6:30 pm comedy slot.

I guess MK14 hasn't heard Dave telling the camera to focus yet, that one always makes me chuckle... and he should definitely avoid AvE's channel. He's Canadian btw...

I suppose audiences sensitivity to 'bad' words, varies.


On topic, it would seem to make sense as Wytnucls suggests for Brymen to rate the meter for 400mA continuous and 600mA peak.

I agree, and thought a similar thing. Many/some 10 Amp multimeter ranges, say something like, 10 Amps continuous, Max 20 Amps for up to 25 seconds, not repeating again for at least 5 minutes.

So, presumably, a similar or vaguely similar specification, such as 450ma continuous, Max 600ma for up to 5 minutes or something. Would make more sense. N.B. I don't know how long or short the times would have to be.
Title: Re: New EEVblog BM786 Multimeter
Post by: Pampalini on February 23, 2021, 08:10:16 pm
Someone wrote me about the magnetic strap having an effect on the beepers loudness.  I was able to replicate it on all the 78x meters I have.   It's not a small effect.  You can make the audio very faint with it.  Really odd.   I have written Brymen about it. 

I don't use these magnetic hangers often and wonder if there are other meters with a similar problem.
Ups... It means I should avoid laying my new BM789 on linear motor or any other magnetic field source :o. I didn't buy magnetic strip only because it was not available yet so my beeper still works. Thanks for the warning.
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on February 23, 2021, 08:20:06 pm
As far as we poms go, it's only really the knitted cardie brigade that gets upset by swearing these days.

I listen to a lot of BBC Radio 4 and it's quite common to hear much stronger language than that in the 6:30 pm comedy slot.

I guess MK14 hasn't heard Dave telling the camera to focus yet, that one always makes me chuckle... and he should definitely avoid AvE's channel. He's Canadian btw...

I suppose audiences sensitivity to 'bad' words, varies.

One tends to adjust one's vocabulary to the nature of one's company.
At work, in the company of people many of whom use the "F word" more or less every other word in a, well, let's call it a "sentence" for the sake of argument, I find myself following suit, and have to consciously moderate myself sometimes.

When speaking with my grandchildren, or my mother for example, I have no difficulty avoiding swear words.



On topic, it would seem to make sense as Wytnucls suggests for Brymen to rate the meter for 400mA continuous and 600mA peak.

I agree, and thought a similar thing. Many/some 10 Amp multimeter ranges, say something like, 10 Amps continuous, Max 20 Amps for up to 25 seconds, not repeating again for at least 5 minutes.

So, presumably, a similar or vaguely similar specification, such as 450ma continuous, Max 600ma for up to 5 minutes or something. Would make more sense. N.B. I don't know how long or short the times would have to be.

It would certainly remove any confusion surrounding the fuse value.
Title: Re: New EEVblog BM786 Multimeter
Post by: Algoma on February 23, 2021, 08:26:11 pm
In follow-up to my AutoRange flickering issue. When its flickering between MOhms and Kohms, it wont take any measurements at all, even with the leads shorted, or a resistor to measure. Though, If I push down gently on the selector switch it will settle and take a measurement. I think it may have likely took some shipping damage, Considering the soiled state of the DHL bag and Squish on the bottom corner of the box, I think it had a bit of a rough transit.

Yes, if I push down gently on the selector switch it works, but if I pull up slightly or tap on the edge of it, off-center, it begins to randomly flicker ranges and produce intermittent random readings. Either bad contacts or possible shipping damage.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 23, 2021, 11:10:18 pm
Someone wrote me about the magnetic strap having an effect on the beepers loudness.  I was able to replicate it on all the 78x meters I have.   It's not a small effect.  You can make the audio very faint with it.  Really odd.   I have written Brymen about it. 
I don't use these magnetic hangers often and wonder if there are other meters with a similar problem.

I could not preproduce wiht the Brymen BM01 hanger for the BM235. Need to try bigger hangers.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 24, 2021, 01:07:04 am
Someone wrote me about the magnetic strap having an effect on the beepers loudness.  I was able to replicate it on all the 78x meters I have.   It's not a small effect.  You can make the audio very faint with it.  Really odd.   I have written Brymen about it. 
I don't use these magnetic hangers often and wonder if there are other meters with a similar problem.

I could not preproduce wiht the Brymen BM01 hanger for the BM235. Need to try bigger hangers.
Try it with your new 786 using their hangers.  The hanger is molded to fit into the meter. 
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 24, 2021, 01:10:48 am
That doesn't seem right.  I wonder what "quite a while" means.

Its intermittent and inconsistent.. 5 seconds to 30 seconds. Diode test mode intermittently flashes low Forward Voltage values, indicating like a shorted diode, even with no leads attached.

I don't see anything like this with the three I have. 
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 24, 2021, 01:11:39 am
Someone wrote me about the magnetic strap having an effect on the beepers loudness.  I was able to replicate it on all the 78x meters I have.   It's not a small effect.  You can make the audio very faint with it.  Really odd.   I have written Brymen about it. 

I don't use these magnetic hangers often and wonder if there are other meters with a similar problem.
Ups... It means I should avoid laying my new BM789 on linear motor or any other magnetic field source :o. I didn't buy magnetic strip only because it was not available yet so my beeper still works. Thanks for the warning.
Remove the magnet and the audio level returns.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 24, 2021, 01:44:26 am
Someone wrote me about the magnetic strap having an effect on the beepers loudness.  I was able to replicate it on all the 78x meters I have.   It's not a small effect.  You can make the audio very faint with it.  Really odd.   I have written Brymen about it. 

I don't use these magnetic hangers often and wonder if there are other meters with a similar problem.
Ups... It means I should avoid laying my new BM789 on linear motor or any other magnetic field source :o. I didn't buy magnetic strip only because it was not available yet so my beeper still works. Thanks for the warning.
Remove the magnet and the audio level returns.

Oh, so it's not permanent damage?
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 24, 2021, 02:17:42 am
Someone wrote me about the magnetic strap having an effect on the beepers loudness.  I was able to replicate it on all the 78x meters I have.   It's not a small effect.  You can make the audio very faint with it.  Really odd.   I have written Brymen about it. 

I don't use these magnetic hangers often and wonder if there are other meters with a similar problem.
Ups... It means I should avoid laying my new BM789 on linear motor or any other magnetic field source :o. I didn't buy magnetic strip only because it was not available yet so my beeper still works. Thanks for the warning.
Remove the magnet and the audio level returns.

Oh, so it's not permanent damage?
It doesn't appear to be in my meters anyway.  You move that magnet around the sweet spot and you can almost silence the meter.   I tried it with the few larger magnets as well.  Same effect, remove them and the meter recovers.   
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 24, 2021, 02:26:19 am
Yep, sure enough:

https://www.youtube.com/watch?v=rZqfp2XKvjE (https://www.youtube.com/watch?v=rZqfp2XKvjE)
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 24, 2021, 02:42:44 am
Crazy.  I haven't looked at any others but many of the beepers look similar from what I remember.  It may be fairly common.   
Title: Re: New EEVblog BM786 Multimeter
Post by: IanB on February 24, 2021, 02:59:44 am
If it's a magnetic beeper, then of course a magnet is going to affect it. But when you use a magnetic strap hanger, surely the magnet is supposed to be on the other end of the hanger than the meter? Why is this even worth talking about?
Title: Re: New EEVblog BM786 Multimeter
Post by: IanB on February 24, 2021, 03:02:33 am
One thing I know about low range current fuses, when I accidentally put 1 A through one, it blew instantly. If I want to measure any current above 100 mA or so, I am going to use the 10 A range. It is far too easy to make a mistake and accidentally over current the thing. And those SIBA fuses are expensive to replace as retail purchases.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 24, 2021, 03:16:03 am
If it's a magnetic beeper, then of course a magnet is going to affect it. But when you use a magnetic strap hanger, surely the magnet is supposed to be on the other end of the hanger than the meter? Why is this even worth talking about?

If you watched that last video where I show the hanger, you can see how it fits into the meter for storage or if you just wanted to use the strap.  It's a very flexible design.  When the magnet is stored, the beeper is not very loud.   I can fully understand why the person brought it up even though you personally don't care about it.  Then again, why post if you don't?
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 24, 2021, 04:25:51 am
One thing I know about low range current fuses, when I accidentally put 1 A through one, it blew instantly. If I want to measure any current above 100 mA or so, I am going to use the 10 A range. It is far too easy to make a mistake and accidentally over current the thing. And those SIBA fuses are expensive to replace as retail purchases.

Yep I do the same. Anything over 50-100mA I'll use the A range, as it's easy to blow and the burden voltage will suck. It's one of the reasons why the 121GW had the 500mA range use the 10A fuse. That way the only the 50mA range and below is protectd by the 400mA fuse.
Title: Re: New EEVblog BM786 Multimeter
Post by: Algoma on February 24, 2021, 03:34:14 pm
In follow-up to my Selection switch issue I had noted with my new BM786, Further testing and operation of the selector switch has gradually improved the operation with use over a few hours. I can no longer cause the misreading and Auto-Range flashing by simply tapping on the switch. It seems likely that the contacts simply needed a bit of a break-in (if anyone else encounters this in the future).
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on February 25, 2021, 04:21:53 am
After leaving the BMH-02 magnet off my meter for a couple of days the beeper has returned to a fairly normal volume again. Brymen really needs to fix this someone might end up touching a live wire or something
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on February 25, 2021, 04:23:22 am
The BMH-02 magnet is incredibly powerful compared to the BMH-01, it easily holds the weight of the entire meter securely
Title: Re: New EEVblog BM786 Multimeter
Post by: Monkeh on February 25, 2021, 04:37:33 am
After leaving the BMH-02 magnet off my meter for a couple of days the beeper has returned to a fairly normal volume again. Brymen really needs to fix this someone might end up touching a live wire or something

Err, if they do that's their fault, not the lack of a beeper.
Title: Re: New EEVblog BM786 Multimeter
Post by: Brumby on February 25, 2021, 05:22:43 am
Err, if they do that's their fault, not the lack of a beeper.
I have to agree.

A positive indication is a positive situation or a false positive.
BUT
A negative indication could mean a negative situation or an equipment failure.

When using ANY tool, all four of the above should be considered!
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 25, 2021, 07:53:39 am
After leaving the BMH-02 magnet off my meter for a couple of days the beeper has returned to a fairly normal volume again. Brymen really needs to fix this someone might end up touching a live wire or something

They are looking into it.
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on February 25, 2021, 11:07:24 am
With nothing better to do I ended up relocating the buzzer further down inside the Meter to a space underneath the LCD screen, problem solved :-+
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on February 25, 2021, 08:47:06 pm
"surely the magnet is supposed to be on the other end of the hanger than the meter?"
It plugs directly onto the back of the meter & the strap optionally attaches to that. The magnet is extremely strong & is particularly useful when working under the bonnet of cars. And it makes a great fridge magnet...
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on February 26, 2021, 02:08:03 am
I've now had two BM786's with issues on the ohms range with errant readinings, possibly switch related.
If anyone else has any issue please let me know.
One, meh, it happens (odd BM235 failures happen in 0.0x percent of cases). Two with a similar issue starts to become more than a coincidence.
Title: Re: New EEVblog BM786 Multimeter
Post by: Andrew McNamara on February 26, 2021, 03:45:16 am
Big Clive lets the odd "F" word slip past his lips.

Really? I don't think I've ever heard him say "Fluke".  ;)
Title: Re: New EEVblog BM786 Multimeter
Post by: MK14 on February 26, 2021, 06:53:12 am
You might get complaints, as you are bordering on swearing, or worse, when the thing broke on you, unexpectedly.
https://youtu.be/OVz9YPfMHuI?t=277

The word bloody, are you serious?  :-//

You said "bugger" as well!

Oh, now I've said it!  :scared:

At the end of the day, it is an 'Engineering' channel, for mainly engineers. So, it should be acceptable.

I'm not sure I follow that logic.

I'm not 100% sure, but I think some of the engineering channels, are considerably worse.

Big Clive lets the odd "F" word slip past his lips.

I know of another (british) toober who has a large selection of 'substitute' words, eg. "What the fudge is that?". Some of them are quite creative.

Weird how the substitutes aren't deemed offensive when the intention/intonation is exactly the same.

Sorry for the late response. You seemed to have edited it, maybe I missed the last section, as I didn't notice the edit (IF that altered or put in the later BigClive bit).

I thought exactly the same thing (BigClive came to mind), I convinced I remember him occasionally releasing the odd 'bad' word here and there. Maybe it seems more acceptable, because he knows the right/acceptable times, as regards British tastes, to do such things, and get away with it.

It is sort of hypocritical of me, but these things are not simple Black and White things.

I suppose it gets into the psychology of why some things cause annoyment, and others don't. Even if scientifically/apparently, the same things sometimes 'annoy' and other times, don't 'annoy'. I guess psychological feelings are NOT always fair or logical (almost by definition).

Some people seem to instill much more tolerance (of such behaviors), than others. Maybe there is some hidden ('Alpha male') or some kind of similar or different psychological effects going on. Which are NOT totally obvious to me (subconscious).
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on February 26, 2021, 08:21:21 am
You might get complaints, as you are bordering on swearing, or worse, when the thing broke on you, unexpectedly.
https://youtu.be/OVz9YPfMHuI?t=277

The word bloody, are you serious?  :-//

You said "bugger" as well!

Oh, now I've said it!  :scared:

At the end of the day, it is an 'Engineering' channel, for mainly engineers. So, it should be acceptable.

I'm not sure I follow that logic.

I'm not 100% sure, but I think some of the engineering channels, are considerably worse.

Big Clive lets the odd "F" word slip past his lips.

I know of another (british) toober who has a large selection of 'substitute' words, eg. "What the fudge is that?". Some of them are quite creative.

Weird how the substitutes aren't deemed offensive when the intention/intonation is exactly the same.

Sorry for the late response. You seemed to have edited it, maybe I missed the last section, as I didn't notice the edit (IF that altered or put in the later BigClive bit).

I thought exactly the same thing (BigClive came to mind), I convinced I remember him occasionally releasing the odd 'bad' word here and there. Maybe it seems more acceptable, because he knows the right/acceptable times, as regards British tastes, to do such things, and get away with it.

It is sort of hypocritical of me, but these things are not simple Black and White things.

I suppose it gets into the psychology of why some things cause annoyment, and others don't. Even if scientifically/apparently, the same things sometimes 'annoy' and other times, don't 'annoy'. I guess psychological feelings are NOT always fair or logical (almost by definition).

Some people seem to instill much more tolerance (of such behaviors), than others. Maybe there is some hidden ('Alpha male') or some kind of similar or different psychological effects going on. Which are NOT totally obvious to me (subconscious).

I don't believe there's any hypocrisy involved; as I mentioned before I believe it's purely contextual on the company you are keeping.

I work as a sparks for a fair sized northern England local authority, and some of my colleagues use the "F" word every other word in a sentence as a matter of course. Indeed, sometimes when they are hunting in their head for what they are trying to say, you can get 2 effings in a row!
This causes me no surprise, though gets boring rather fast.

On the other hand I have been talking to well educated, besuited people, and am shocked when they drop an F-bomb out of nowhere.

As ever, YMMV...
Title: Re: New EEVblog BM786 Multimeter
Post by: MK14 on February 26, 2021, 08:33:34 am
I don't believe there's any hypocrisy involved; as I mentioned before I believe it's purely contextual on the company you are keeping.

I work as a sparks for a fair sized northern England local authority, and some of my colleagues use the "F" word every other word in a sentence as a matter of course. Indeed, sometimes when they are hunting in their head for what they are trying to say, you can get 2 effings in a row!
This causes me no surprise, though gets boring rather fast.

On the other hand I have been talking to well educated, besuited people, and am shocked when they drop an F-bomb out of nowhere.

As ever, YMMV...


I know exactly what you mean. I've experienced and/or seen the same thing, where a person emits multiple F-bombs, in succession, because they are (obviously) going through various solutions and/or concepts about what has just happened or is going on.
I think, some people have the experience/self-control/decency to detect when the company (people) they are with, can tolerate swearing or NOT. So, will moderate their language, as necessary. People who can't/won't do that, may find that the people that like to be with them and/or jobs they can get, are limited, compared to people who can moderate their activities.

My reason for being concerned with the *bleep* word(s), in the video on this multimeter. Are in case other viewers, also don't like such language and/or are with younger viewers. The youtubers (content creators), can say "It is my channel, I will do what I like". But, it could limit their viewership.

Some technical channels, seem to never omit swear words. Which (possibly), have a wider/broader audience base, as a result (speculation). On the other hand, some viewers, may even prefer the odd (real-life) remarks. So, I suppose it is horses for courses.
Title: Re: New EEVblog BM786 Multimeter
Post by: schwaggins on February 26, 2021, 10:57:47 am
I've now had two BM786's with issues on the ohms range with errant readinings, possibly switch related.
If anyone else has any issue please let me know.
One, meh, it happens (odd BM235 failures happen in 0.0x percent of cases). Two with a similar issue starts to become more than a coincidence.

Check the range selector screws arent loose on the back of the board
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on February 26, 2021, 01:38:05 pm
I don't believe there's any hypocrisy involved; as I mentioned before I believe it's purely contextual on the company you are keeping.

I work as a sparks for a fair sized northern England local authority, and some of my colleagues use the "F" word every other word in a sentence as a matter of course. Indeed, sometimes when they are hunting in their head for what they are trying to say, you can get 2 effings in a row!
This causes me no surprise, though gets boring rather fast.

On the other hand I have been talking to well educated, besuited people, and am shocked when they drop an F-bomb out of nowhere.

As ever, YMMV...


I know exactly what you mean. I've experienced and/or seen the same thing, where a person emits multiple F-bombs, in succession, because they are (obviously) going through various solutions and/or concepts about what has just happened or is going on.
I think, some people have the experience/self-control/decency to detect when the company (people) they are with, can tolerate swearing or NOT. So, will moderate their language, as necessary. People who can't/won't do that, may find that the people that like to be with them and/or jobs they can get, are limited, compared to people who can moderate their activities.

My reason for being concerned with the *bleep* word(s), in the video on this multimeter. Are in case other viewers, also don't like such language and/or are with younger viewers. The youtubers (content creators), can say "It is my channel, I will do what I like". But, it could limit their viewership.

Some technical channels, seem to never omit swear words. Which (possibly), have a wider/broader audience base, as a result (speculation). On the other hand, some viewers, may even prefer the odd (real-life) remarks. So, I suppose it is horses for courses.

When I started to post on YT, it became quickly apparent that filtering posts for certain key words would remove most of the noise.   This was far more effective than say banning individual accounts.   Based on their command of the English language and apparent lack of education, I assume most were children which my channel certainly doesn't target.   So I just made it clear from the start, keep your language clean and don't use links if you decide to post.   Links were added to the filter as there were people how want to use the channel for their own gains (ads).   I think YT now has it's own filters.   

Anyone who caught my recent clip where the dialog was only a single word repeated several times may consider me being hypocritical by using the filters.  Personally I don't care about a persons choice of colorful words.  I am also against censorship and would have left all the filters off but opted for a higher signal to noise ratio.

I have not considered how adding these filters has effected the viewership, nor do I care.  It's a small channel and the goal was never to use it for monetary purposes so I can afford to do as I like with it.
Title: Re: New EEVblog BM786 Multimeter
Post by: MK14 on February 26, 2021, 01:55:11 pm
When I started to post on YT, it became quickly apparent that filtering posts for certain key words would remove most of the noise.   This was far more effective than say banning individual accounts.   Based on their command of the English language and apparent lack of education, I assume most were children which my channel certainly doesn't target.   So I just made it clear from the start, keep your language clean and don't use links if you decide to post.   Links were added to the filter as there were people how want to use the channel for their own gains (ads).   I think YT now has it's own filters.   

Anyone who caught my recent clip where the dialog was only a single word repeated several times may consider me being hypocritical by using the filters.  Personally I don't care about a persons choice of colorful words.  I am also against censorship and would have left all the filters off but opted for a higher signal to noise ratio.

I have not considered how adding these filters has effected the viewership, nor do I care.  It's a small channel and the goal was never to use it for monetary purposes so I can afford to do as I like with it.

Your short, single repeating word, doesn't seem to bother me (but would arguably still be better, in some peoples minds, to leave out such colourful language). There was a rather big/dramatic accident with your stuff, and hopefully rare accident, which could have messed up many hours of work. Damaged expensive equipment, and hurt your foot (depending on where it landed). So, I can understand the colourful word(s).
Anyway, you gain many valuable brownie points, for keeping the word, very quiet (showing respect for your language).
It is the people who overuse, such expletives, that especially bother me. E.g. Every other word, begins with f and you can probably guess the rest of the letters.

If the youtuber was a medical Doctor and/or Professor and/or top expert, I wouldn't expect them to omit any bad words, at all. But there are probably exceptions, even in those cases.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on February 26, 2021, 07:31:34 pm
I work as a sparks for a fair sized northern England local authority, and some of my colleagues use the "F" word every other word in a sentence as a matter of course. Indeed, sometimes when they are hunting in their head for what they are trying to say, you can get 2 effings in a row!
This causes me no surprise, though gets boring rather fast.

Yep. I don't mind swearing except when it's the only adjective people have.

On the other hand I have been talking to well educated, besuited people, and am shocked when they drop an F-bomb out of nowhere.

Knowing how and when to swear is a useful skill.

Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on March 12, 2021, 02:50:02 pm
Well this discussion about the F word is well placed.    My 786 arrived Wednesday and as I walked in the house with my new pride and joy I realized it was a bit chilly.   Sure enough the furnace had failed literally tripping the main breaker.    Once I verified that there was no heat for the night I hit the sack to tired to really care.   

So no unpacking videos, the meter is already dirty from work on the furnace.   The next day I quickly determined that I need a new furnbace motor F!

It probably isn't the best way to learn about a new instrument, that is laying on your back, on concrete, next to a dirty furnace.  In any event there are  things that stand out almost immediately.   
In any event this meter fits a need and I like the idea that I can help in a small way to keep EEVBlog on the air.   
Title: Re: New EEVblog BM786 Multimeter
Post by: xvf22 on March 16, 2021, 09:57:07 pm
Hmm, just got my meter and I like it, continuity is great and the better refresh rate and digits help but having a bit of an issue. My 2709B meter from long ago seems to have no trouble lighting LEDs in circuit. The BM786 can do it on a naked LEDs but any in circuit LEDs (arduinos etc) I've tried they don't light up.
Am I missing something and/or being stupid?

Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on March 16, 2021, 10:50:02 pm
Hmm, just got my meter and I like it, continuity is great and the better refresh rate and digits help but having a bit of an issue. My 2709B meter from long ago seems to have no trouble lighting LEDs in circuit. The BM786 can do it on a naked LEDs but any in circuit LEDs (arduinos etc) I've tried they don't light up.
Am I missing something and/or being stupid?

That would be the drive current and/or compliance voltage. All meters are different.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on March 16, 2021, 11:32:56 pm
Am I missing something and/or being stupid?

Every meter is different.

Try using your old meter to measure the voltage/current that the BM786 is applying to that LED (especially the current - it's a constant current source in diode mode).

Then switch it around and use the BM786 to measure the current/voltage that the old meter is applying to that LED.

Title: Re: New EEVblog BM786 Multimeter
Post by: bdunham7 on March 16, 2021, 11:35:09 pm
Hmm, just got my meter and I like it, continuity is great and the better refresh rate and digits help but having a bit of an issue. My 2709B meter from long ago seems to have no trouble lighting LEDs in circuit. The BM786 can do it on a naked LEDs but any in circuit LEDs (arduinos etc) I've tried they don't light up.
Am I missing something and/or being stupid?

What does the meter read when it is not successful at lighting a LED?
Title: Re: New EEVblog BM786 Multimeter
Post by: Microdoser on March 21, 2021, 10:18:20 pm
I work as a sparks for a fair sized northern England local authority, and some of my colleagues use the "F" word every other word in a sentence as a matter of course. Indeed, sometimes when they are hunting in their head for what they are trying to say, you can get 2 effings in a row!
This causes me no surprise, though gets boring rather fast.

Yep. I don't mind swearing except when it's the only adjective people have.

On the other hand I have been talking to well educated, besuited people, and am shocked when they drop an F-bomb out of nowhere.

Knowing how and when to swear is a useful skill.

I was watching Frankie Boyle the other day, and he said that in Scotland, the 'F' word is used as a grammatical cue to let you know there is a noun coming next   :D
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on March 25, 2021, 04:17:23 am
There is new BM786 firmware 78606
Bug fixed is
Quote
In the condition of being locked at 60.000k (or 600.00k) Ohm manual range, while input test leads are short, LCD reading may sometimes display OL, 67.2xx kOhm (or 672.xx kOhm), .... for few seconds before displaying correct 00.000 kOhm (or 000.00kOhm). User will not see this phenomenon in the condition of Auto-ranging.
New stock I got today has the new firmware.

BTW I only got 60 units, as global component shortages are still taking their toll on production.
Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on March 26, 2021, 01:58:31 pm
There is new BM786 firmware 78606
Bug fixed is
Quote
In the condition of being locked at 60.000k (or 600.00k) Ohm manual range, while input test leads are short, LCD reading may sometimes display OL, 67.2xx kOhm (or 672.xx kOhm), .... for few seconds before displaying correct 00.000 kOhm (or 000.00kOhm). User will not see this phenomenon in the condition of Auto-ranging.
New stock I got today has the new firmware.
Interesting, are the meters easily field upgradeable?
Quote

BTW I only got 60 units, as global component shortages are still taking their toll on production.

Well that sucks!    I'm actually surprised that a meter of this type would be using silicon that comes off the state of the art lines that are backed up.
Title: Re: New EEVblog BM786 Multimeter
Post by: NoisyBoy on March 26, 2021, 06:45:08 pm
I just love Dave’s transparency and integrity when it comes to product info from the EEVBlog store.

Unfortunately, based on Joe’s video, it is not field upgradable and a recalibration is required by Bryman.  That is one reason why I like bench meters like the 3446xA compared to the old 34401A.  They provide regular firmware update without the need to recalibrate.

Dave, I like the meter, perhaps one thing you could communicate back to the manufacturer is the ability to do field firmware upgrade would have provided a great differentiation that all buyers would love to have, and helps to reduce their warranty cost.
Title: Re: New EEVblog BM786 Multimeter
Post by: bdunham7 on March 26, 2021, 07:07:53 pm
compared to the old 34401A.  They provide regular firmware update without the need to recalibrate.

I can't imagine what you would want to update on a 34401A.   :)
Adding features is a nice idea, but I'm not so thrilled about manufacturers shipping half-baked stuff knowing they can maybe fix it later if they have to--if they are still around and if they still care. 

Quote
Dave, I like the meter, perhaps one thing you could communicate back to the manufacturer is the ability to do field firmware upgrade would have provided a great differentiation that all buyers would love to have, and helps to reduce their warranty cost.

I think the issue is that they want their code protected.
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on March 26, 2021, 07:45:13 pm
compared to the old 34401A.  They provide regular firmware update without the need to recalibrate.

I can't imagine what you would want to update on a 34401A.   :)
Adding features is a nice idea, but I'm not so thrilled about manufacturers shipping half-baked stuff knowing they can maybe fix it later if they have to--if they are still around and if they still care. 

Quote
Dave, I like the meter, perhaps one thing you could communicate back to the manufacturer is the ability to do field firmware upgrade would have provided a great differentiation that all buyers would love to have, and helps to reduce their warranty cost.

I think the issue is that they want their code protected.

I think UEI were are pretty protective of the 121GW software, still has a firmware update facility. Probably more to do with the cost of including the physical parts to enable connecting to whatever update media is used.
Title: Re: New EEVblog BM786 Multimeter
Post by: IanB on March 26, 2021, 10:49:07 pm
Dave, I like the meter, perhaps one thing you could communicate back to the manufacturer is the ability to do field firmware upgrade would have provided a great differentiation that all buyers would love to have, and helps to reduce their warranty cost.

From Joe's testing experience, it seems the firmware is burned into ROM. I suppose that making the firmware field-upgradable would increase the manufacturing cost. They can't provide an external USB port for safety reasons, and few people would be able to open up the case, connect to an internal programming header, and use a special programmer to burn the new firmware (at the risk of bricking the device if they got it wrong).

Somehow I imagine it just isn't practical to provide a user-upgrade path.
Title: Re: New EEVblog BM786 Multimeter
Post by: bdunham7 on March 26, 2021, 11:25:05 pm
They can't provide an external USB port for safety reasons, and few people would be able to open up the case, connect to an internal programming header, and use a special programmer to burn the new firmware (at the risk of bricking the device if they got it wrong).

For some reason I thought this meter had PC-COM.  But are the PC-COM equipped Brymen meters
 flashable?
Title: Re: New EEVblog BM786 Multimeter
Post by: NoisyBoy on March 26, 2021, 11:54:21 pm
I certainly am not proposing putting in a field upgradable design just to enable the ability to deliver poor quality firmware.  And I can certainly understand the challenge in adding such capability.  My point is just that if it is feasible, it would be a nice feature to add. 

I also agree with the 34401A stability, I have two with the final firmware, and those meters are rock solid, but that came with a decade + of updates.  Mine has the final firmware, version 11, I am not sure how much was fixed in the previous 10 versions, but clearly even in the case of 34401A, HP/Agilent saw a need for firmware upgrades over the years.  However, in the case of the 3446xA, they were able to add capacitance measurement to the early build later on, and each firmware release addressed uncommon problems that I will never encounter in my use.  It is nice to know that I have patched it so it will not happen to me if that use case were to come up.

Anyway, back to the 786, I was able to get some random numbers to come up by shorting the leads, but with 50+ attempts on those ranges, I was never able to get an erroneous reading that last for more than a second.  They were all transient readings that lasted for less than 1 second. 

I can actually make the same behavior occur on my Fluke 179 with the latest firmware in manual range.  With the two 34401A I own with firmware 11-05-03, they also generate a split second random reading in manual range.  The only difference is these meters goes back to 0 faster, where 786 could sometimes takes close to 1 second. 

The only meter that shows the right reading in manual range are the 34461A and 34465A, they both display the proper value at every try.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on March 27, 2021, 01:34:35 am
I just love Dave’s transparency and integrity when it comes to product info from the EEVBlog store.
He learned from the 121GW revision being sold on his shop with an old HW revision board - not saying he did this on purpose, but it annoyed a bunch of people at the time.


Unfortunately, based on Joe’s video, it is not field upgradable and a recalibration is required by Bryman.  That is one reason why I like bench meters like the 3446xA compared to the old 34401A.  They provide regular firmware update without the need to recalibrate.

I doubt Brymen is using OTP, but instead Flash with a burned JTAG fuse to prevent any access. That said, I recall Dave saying they were pretty tight in memory, which makes sense as a reflasher via serial requires a small bootloader which consumes memory. A ROM bootloader could be used, but it would be easier to hack.

They are not the only ones: Fluke also does not allow this. Keysight does.
Title: Re: New EEVblog BM786 Multimeter
Post by: bdunham7 on March 27, 2021, 01:40:08 am
Fluke also does not allow this.

I'm not clear--Fluke does not allow what?
Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on March 27, 2021, 02:50:12 am
compared to the old 34401A.  They provide regular firmware update without the need to recalibrate.

I can't imagine what you would want to update on a 34401A.   :)
Adding features is a nice idea, but I'm not so thrilled about manufacturers shipping half-baked stuff knowing they can maybe fix it later if they have to--if they are still around and if they still care. 

That is not the point and never has been the point of having upgradeable software.   Are you seriously implying you want to be stuck with bugs forever.
Quote
Quote
Dave, I like the meter, perhaps one thing you could communicate back to the manufacturer is the ability to do field firmware upgrade would have provided a great differentiation that all buyers would love to have, and helps to reduce their warranty cost.

I think the issue is that they want their code protected.

I don't doubt that one bit.    However It would be nice to see somebody offer up an open sourced DMM.   We need this as users because of the one problem that is rather huge in the test equipment industry, that is a lot of manufactures just don't last.   That is a company will flop before its hardware has ran through a reasonable life span.    Beyond that I'm still amazed that we don't have scriptable instruments from the big manufactures.
Title: Re: New EEVblog BM786 Multimeter
Post by: Kleinstein on March 27, 2021, 06:36:02 am
A DMM should have reliable software from the start.  Wrong reading may pose a safety problem, so it needs some security measures.  This would be a problem with a open source DMM, or even one with open access to the software.

At least the basic functions of a handheld DMM are not that complicated and can be tested relatively easy. It gets more complicated only with more special functions like graphing, statistics and similar.
If really wanted a suitable place for a connector to allow a SW update would be in the battery compartment.
Not having the possibility to change the SW easy forces the manufacturers to get it right. For a limited SW complexity there is a chance to have bug free software.

Getting intermediate numbers when changing the input signal is normal. The DMM reading is an average over some time and some intermedate number is correct - not random, just hard to control manually. The bench DMMs tend to be faster in the default settings and thus have the transients less visible.
Title: Re: New EEVblog BM786 Multimeter
Post by: 2N3055 on March 27, 2021, 08:40:57 am
I don't doubt that one bit.    However It would be nice to see somebody offer up an open sourced DMM.   We need this as users because of the one problem that is rather huge in the test equipment industry, that is a lot of manufactures just don't last.   That is a company will flop before its hardware has ran through a reasonable life span.    Beyond that I'm still amazed that we don't have scriptable instruments from the big manufactures.

There are literally hundreds of open source multimeters on the Internet. And they all went nowhere. Not to mention how safe is to make something you poke into dangerous voltages that Arduino maker will "hack and make better".

And what's with "don't have scriptable instruments"? All of them are, if they have any kind of interface. You need Raspberry PI, small screen, and write Python scripts for days... Graphing, logging, everything. I have a network share mapped, so files are accessible from PCs too... Ethernet, serial, Bluetooth, GPIB connectivity, you name it.
Also, DMM6500 from Keithley has built in scripting language and rather big screen.   OTOH, unfortunately, it is also a living proof that Linux can also bluescreen all the time if you write crappy software...
Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on March 27, 2021, 09:48:50 pm
I don't doubt that one bit.    However It would be nice to see somebody offer up an open sourced DMM.   We need this as users because of the one problem that is rather huge in the test equipment industry, that is a lot of manufactures just don't last.   That is a company will flop before its hardware has ran through a reasonable life span.    Beyond that I'm still amazed that we don't have scriptable instruments from the big manufactures.

There are literally hundreds of open source multimeters on the Internet. And they all went nowhere. Not to mention how safe is to make something you poke into dangerous voltages that Arduino maker will "hack and make better".
That pretty much highlights that there are no true open source multimeters.   Further there is a lot more to the world of open source and even open hardware than Arduino.   I sometimes see Arduino as enablement for idiots but that doesn't mean everybody that put an Arduino to good use is an idiot.
Quote
And what's with "don't have scriptable instruments"? All of them are, if they have any kind of interface.
Having an interface doesn't make the meter itself scriptable.
Quote
You need Raspberry PI, small screen, and write Python scripts for days... Graphing, logging, everything. I have a network share mapped, so files are accessible from PCs too... Ethernet, serial, Bluetooth, GPIB connectivity, you name it.
Also, DMM6500 from Keithley has built in scripting language and rather big screen.   OTOH, unfortunately, it is also a living proof that Linux can also bluescreen all the time if you write crappy software...
So you have one high end meter to consider here.   As for a blue screens you are right that crappy software is a problem, but even quality software will have bugs.   That is why field up-gradable instruments makes lots of sense to me.    It is almost impossible to ship reasonably complex software without bugs.

What is interesting to me, with respect to Linux and much of the software that runs there, is just how good it has become.    Yes there are crappy apps, that are delivered by rather poor programmers, but that stuff doesn't stay in circulation long.    Either programmer (often the project leader) gets better at programming or something turns up to replace it.    Contrast this with Windows when you can get stuck with a crappy app with no replacement in sight, nor a way to get it fixed.

Is open source always the right answer, nope not saying that.   However it has done really well in some case such as low end logic analyzers.   The industry would benefit from more such successes.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on March 28, 2021, 10:33:41 am
Dave, I like the meter, perhaps one thing you could communicate back to the manufacturer is the ability to do field firmware upgrade would have provided a great differentiation that all buyers would love to have, and helps to reduce their warranty cost.

I've already did that when I first heard that it was possible with gthis new design (the BM235 and others use OTP parts). But they clearly don't want users upgrading the firmware. If you want an answer on why you'll have to ask them directly, I don't know.
Ultimately I (as a dealer) will have the ability to do firmware upgrades once I get the hardware to do so, but it's all under NDA I'm afraid.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on March 28, 2021, 10:36:11 am
They can't provide an external USB port for safety reasons, and few people would be able to open up the case, connect to an internal programming header, and use a special programmer to burn the new firmware (at the risk of bricking the device if they got it wrong).

For some reason I thought this meter had PC-COM.  But are the PC-COM equipped Brymen meters
 flashable?

No they aren't. I believe the BM78x series is the first to use a re-programmable processor.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on March 28, 2021, 10:40:31 am
I doubt Brymen is using OTP, but instead Flash with a burned JTAG fuse to prevent any access.

Maybe, but I have been told the BM235 is OTP. And given that during development they were wondering if they could fit a couple of extra features I wanted in the IIRC hundred bytes or something they had left in the memory, I'm fairly confident it's one of those little known smal memory OTP processors.
[/quote]
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on March 28, 2021, 10:43:34 am
If really wanted a suitable place for a connector to allow a SW update would be in the battery compartment.

That's where it is on the BM786. Or at least that's what I assume it is they haven't given me the programmer hardware or instructions yet. But there is a mystery header in the battery compartment.
Title: Re: New EEVblog BM786 Multimeter
Post by: ogdento on April 17, 2021, 06:22:18 am
I saw that Dave and some others checked various headers on the unit and got no data coming out, but I noticed that the lcd driver (HY2613C) has an i2c interface... are the sda/scl lines exposed on any pads/test points? 

If so, maybe the data going to the lcd could be read??  (sortof how you can read the older brymens lcd data via the IR adapter)
Title: Re: New EEVblog BM786 Multimeter
Post by: Microdoser on April 17, 2021, 11:42:49 am
Dave, I like the meter, perhaps one thing you could communicate back to the manufacturer is the ability to do field firmware upgrade would have provided a great differentiation that all buyers would love to have, and helps to reduce their warranty cost.

I've already did that when I first heard that it was possible with gthis new design (the BM235 and others use OTP parts). But they clearly don't want users upgrading the firmware. If you want an answer on why you'll have to ask them directly, I don't know.
Ultimately I (as a dealer) will have the ability to do firmware upgrades once I get the hardware to do so, but it's all under NDA I'm afraid.

I suspect that, in part, they don't want third party firmware being installed.
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on April 17, 2021, 12:06:23 pm
I suspect that, in part, they don't want third party firmware being installed.

I suspect that the meter's CAT rating depends on the firmware so they don't want anybody compromising that.

Title: Re: New EEVblog BM786 Multimeter
Post by: Microdoser on April 17, 2021, 04:39:45 pm
I suspect that, in part, they don't want third party firmware being installed.

I suspect that the meter's CAT rating depends on the firmware so they don't want anybody compromising that.

That would be one of the reasons they don't want third party firmware installed, yes.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on April 19, 2021, 01:17:30 am
If really wanted a suitable place for a connector to allow a SW update would be in the battery compartment.
That's where it is on the BM786. Or at least that's what I assume it is they haven't given me the programmer hardware or instructions yet. But there is a mystery header in the battery compartment.

Mystery battery compartment header confirmed as the programming port (obviously).
I am also now in possesion of the programmer so am able to update stock on hand if a firmware update comes out. Have not tried it yet though.
Please do not ask for any details, I am not able to reveal any info about it.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on April 19, 2021, 01:22:51 am
I saw that Dave and some others checked various headers on the unit and got no data coming out, but I noticed that the lcd driver (HY2613C) has an i2c interface... are the sda/scl lines exposed on any pads/test points? 
If so, maybe the data going to the lcd could be read??  (sortof how you can read the older brymens lcd data via the IR adapter)

Photos: https://www.flickr.com/photos/eevblog/albums/72157718973141297 (https://www.flickr.com/photos/eevblog/albums/72157718973141297)
Title: Re: New EEVblog BM786 Multimeter
Post by: AVGresponding on April 19, 2021, 05:32:37 pm
If really wanted a suitable place for a connector to allow a SW update would be in the battery compartment.
That's where it is on the BM786. Or at least that's what I assume it is they haven't given me the programmer hardware or instructions yet. But there is a mystery header in the battery compartment.

Mystery battery compartment header confirmed as the programming port (obviously).
I am also now in possesion of the programmer so am able to update stock on hand if a firmware update comes out. Have not tried it yet though.
Please do not ask for any details, I am not able to reveal any info about it.

I am curious about the position on non-updated meters already existing in the wild. Do you anticipate some sort of shipping-them-there-and-back program to update them, or would that be logistically impossible?
Title: Re: New EEVblog BM786 Multimeter
Post by: ogdento on April 19, 2021, 06:46:26 pm
Thanks Dave,
I can see the SCL/SDA lines going from driver pins 9/10 to the R210/R211 (1k?) resistors on the board bottom.  Not sure if those are pullups, but I can't see where they go after.  I guess it would be interesting to play around with, but may be silly to hack in a data-output port.

[attach=1]

[attach=2]
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on April 19, 2021, 08:51:52 pm
Mystery battery compartment header confirmed as the programming port (obviously).
I am also now in possesion of the programmer so am able to update stock on hand if a firmware update comes out. Have not tried it yet though.
Aha! I called it!  ;D
(minus the blown JTAG fuse)

I doubt Brymen is using OTP, but instead Flash with a burned JTAG fuse to prevent any access.

Maybe, but I have been told the BM235 is OTP. And given that during development they were wondering if they could fit a couple of extra features I wanted in the IIRC hundred bytes or something they had left in the memory, I'm fairly confident it's one of those little known smal memory OTP processors.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on April 19, 2021, 11:05:15 pm
I am curious about the position on non-updated meters already existing in the wild. Do you anticipate some sort of shipping-them-there-and-back program to update them, or would that be logistically impossible?

Logistically and financially not viable. Consider the BM78x series the same as all other Brymen meters, non-upgradable.
Title: Re: New EEVblog BM786 Multimeter
Post by: jayjr1105 on May 01, 2021, 11:30:05 pm
After regrettably selling my BM235, I bit the bullet on this meter.  Yes it's probably overkill for my hobby needs but I was sick of chasing the unicorn $50-100 "perfect" dmm.  BTW, is there no official eevblog video on this meter yet?  Would have been nice to see a thorough review of it even if it's your own product.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on May 02, 2021, 01:16:06 am
Two good reviews are at reach:

https://duckduckgo.com/?q=bm786+review&t=fpas&iax=videos&ia=videos
Title: Re: New EEVblog BM786 Multimeter
Post by: wizard69 on May 03, 2021, 10:44:20 pm
You will never regret having a "better than needed meter".   Even at the hobby end of the world a meter is such a basic instrument, that lasts a very long time, the cost isn't as big of a deal as it is with other products.   There are actually some very useful meters in the $50 to $100 range, for a beginner or hobbyist, but I still see benefit in moving up market.

I like to think of myself as being thrifty and cut corners on a lot of stuff for my pursuits.   However I'm pleased with my 786 as it is good product and I manage to support EEVblog a bit with the purchase.   Win Win. 

After regrettably selling my BM235, I bit the bullet on this meter.  Yes it's probably overkill for my hobby needs but I was sick of chasing the unicorn $50-100 "perfect" dmm.  BTW, is there no official eevblog video on this meter yet?  Would have been nice to see a thorough review of it even if it's your own product.
Title: Re: New EEVblog BM786 Multimeter
Post by: jayjr1105 on May 05, 2021, 11:58:50 pm
You will never regret having a "better than needed meter".   Even at the hobby end of the world a meter is such a basic instrument, that lasts a very long time, the cost isn't as big of a deal as it is with other products.   There are actually some very useful meters in the $50 to $100 range, for a beginner or hobbyist, but I still see benefit in moving up market.

I like to think of myself as being thrifty and cut corners on a lot of stuff for my pursuits.   However I'm pleased with my 786 as it is good product and I manage to support EEVblog a bit with the purchase.   Win Win. 

After regrettably selling my BM235, I bit the bullet on this meter.  Yes it's probably overkill for my hobby needs but I was sick of chasing the unicorn $50-100 "perfect" dmm.  BTW, is there no official eevblog video on this meter yet?  Would have been nice to see a thorough review of it even if it's your own product.
Yeah you pretty much nailed it.  I'm frugal with a lot of things but some tools and toys I like to splurge on if it's going to be high quality and last a long time.  Here is my new "toy"
(https://i.imgur.com/KZOwOMQ.png)
Title: Re: New EEVblog BM786 Multimeter
Post by: ceut on May 31, 2021, 10:05:23 pm
Hello,
I was about ordering the BM786, but when I saw the price difference with the BM789: I switched to the 789.
Also I use the Z-Low of my U1272A (very slowwww about 1read/s with low resolution, whereas all the other function are super fast with high resolution and I love that), and the "Auto" of my BM257s (full speed and resolution) for big capacitor discharge and other low-Z checking.

So here is my question: why EEVblog meter is not the 789 model ?  :(

And I like the blue thing very much... :-[
Title: Re: New EEVblog BM786 Multimeter
Post by: J-R on May 31, 2021, 11:36:31 pm
I also made the same decision and picked up the BM789 for the extra features. 

I think Dave wanted a model number exclusive to him and at a specific price point.  Brymen may have wanted the top model for themselves.
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on June 01, 2021, 01:01:40 am
Hello,
I was about ordering the BM786, but when I saw the price difference with the BM789: I switched to the 789.
Also I use the Z-Low of my U1272A (very slowwww about 1read/s with low resolution, whereas all the other function are super fast with high resolution and I love that), and the "Auto" of my BM257s (full speed and resolution) for big capacitor discharge and other low-Z checking.
So here is my question: why EEVblog meter is not the 789 model ?  :(

It's because Brymen are incredibly loyal to their distributors, even if those distributors are crap.
If they already have an official distributor in a specific country and they have an agreement with them for a particular model, then they will not sell that model to any other distributor.
I sell orders of magnitude more meters than the other official Australian Brymen distributor, but they are loyal to them, so they won't let me sell any other meter they are selling.
So Brymen created the BM786 model specifically for me in order to get around this limitation, that was never supposed to be on the market otherwise.
For example, for more than 5 years I've wanted to sell the BM869 but they will not sell it to me.
Title: Re: New EEVblog BM786 Multimeter
Post by: Caliaxy on June 01, 2021, 01:26:50 am
It's because Brymen are incredibly loyal to their distributors, even if those distributors are crap.
If they already have an official distributor in a specific country and they have an agreement with them for a particular model, then they will not sell that model to any other distributor.
I sell orders of magnitude more meters than the other official Australian Brymen distributor, but they are loyal to them, so they won't let me sell any other meter they are selling.
So Brymen created the BM786 model specifically for me in order to get around this limitation, that was never supposed to be on the market otherwise.
For example, for more than 5 years I've wanted to sell the BM869 but they will not sell it to me.

Idea: would they let you sell blue holsters for the meters they don't let you sell? Then people would buy whatever meter they want (BM789, BM869 etc) from whoever sells it and the holster from you, to support eevblog. You could sell blue holsters for every meter you endorse  ;D
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on June 01, 2021, 01:30:05 am
It's because Brymen are incredibly loyal to their distributors, even if those distributors are crap.
If they already have an official distributor in a specific country and they have an agreement with them for a particular model, then they will not sell that model to any other distributor.
I sell orders of magnitude more meters than the other official Australian Brymen distributor, but they are loyal to them, so they won't let me sell any other meter they are selling.

Is that why they have such poor representation in the USA?

(ie. Greenlee have some sort of a licensing deal)
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on June 01, 2021, 01:42:12 am
It's because Brymen are incredibly loyal to their distributors, even if those distributors are crap.
If they already have an official distributor in a specific country and they have an agreement with them for a particular model, then they will not sell that model to any other distributor.
I sell orders of magnitude more meters than the other official Australian Brymen distributor, but they are loyal to them, so they won't let me sell any other meter they are selling.
Is that why they have such poor representation in the USA?
(ie. Greenlee have some sort of a licensing deal)

Almost certainly.
If you are in the US, contact Brymen and try to order 500 meters to resell and see what they say.

Back when I originally wanted to resell a Brymen I wanted the BM257, but I was told I couldn't have it because another dealer already sells it. Then they told me about the BM235 which had just started development, and hadn't been offered to them yet, so I had to wait more than a year for that model to be released before I could sell anything Brymen.
Title: Re: New EEVblog BM786 Multimeter
Post by: totalnoob on June 01, 2021, 11:21:19 am
Is that why they have such poor representation in the USA?

(ie. Greenlee have some sort of a licensing deal)

And Greenlee has a hell of a mark up on their meters, too, which doesn't help any. 
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on June 01, 2021, 11:28:06 am
Is that why they have such poor representation in the USA?

(ie. Greenlee have some sort of a licensing deal)

And Greenlee has a hell of a mark up on their meters, too, which doesn't help any.

But they don't sell direct do they? So they need a markup on top of that for their retailers.
But I can confirm that the markup is very large.
I do very well selling Brymen meters, even at my reasonable prices.
Title: Re: New EEVblog BM786 Multimeter
Post by: rsjsouza on June 01, 2021, 01:18:05 pm
Is that why they have such poor representation in the USA?

(ie. Greenlee have some sort of a licensing deal)

And Greenlee has a hell of a mark up on their meters, too, which doesn't help any.

But they don't sell direct do they? So they need a markup on top of that for their retailers.
But I can confirm that the markup is very large.
I do very well selling Brymen meters, even at my reasonable prices.
The markup for a DM-860A (BM869 equivalent) is comparatively high (20% when compared to TME), although Tequipment sells them for US$313.00 (US$295 with the 6% EEV discount) which, with shipping (for me it is about US$14.00) it does not necessarily break the bank, as Greenlee promises a "lifetime warranty" (I didn't look at the fine print).

https://www.tequipment.net/Greenlee/DM-860A/Multimeters/?search=true (https://www.tequipment.net/Greenlee/DM-860A/Multimeters/?search=true)

As an individual user I would go for the TME prices but, if you are a company or can have a tax break of sorts, it would not be tantamount to legalized theft...  :-DD
Title: Re: New EEVblog BM786 Multimeter
Post by: bdunham7 on June 01, 2021, 01:18:24 pm
But they don't sell direct do they? So they need a markup on top of that for their retailers.
But I can confirm that the markup is very large.

They do sell direct, although not exclusively.  Greenlee is a professional electrician's tool seller, so a lot of their product will be sold through electrician's supply houses.

https://www.greenleestore.com/search?type=product&options%5Bprefix%5D=last&q=multimeter (https://www.greenleestore.com/search?type=product&options%5Bprefix%5D=last&q=multimeter)

I don't think those prices are outrageous since they include free shipping and a lifetime warranty that probably isn't backed by Brymen.  Note that they are sold out of almost everything...

Then there's TEquipment, after the 6% EEVblog discount the 869 equivalent is under $300 and includes a nice bag.

https://www.tequipment.net/Greenlee/DM-860A/Multimeters/?v=65116 (https://www.tequipment.net/Greenlee/DM-860A/Multimeters/?v=65116)
Title: Re: New EEVblog BM786 Multimeter
Post by: ceut on June 03, 2021, 08:44:18 pm
Quote from: EEVblog on June 01, 2021, 01:01:40 am (https://www.eevblog.com/forum/index.php?topic=256926.msg3580260#msg3580260)
It's because Brymen are incredibly loyal to their distributors, even if those distributors are crap.
If they already have an official distributor in a specific country and they have an agreement with them for a particular model, then they will not sell that model to any other distributor.
I sell orders of magnitude more meters than the other official Australian Brymen distributor, but they are loyal to them, so they won't let me sell any other meter they are selling.
So Brymen created the BM786 model specifically for me in order to get around this limitation, that was never supposed to be on the market otherwise.
For example, for more than 5 years I've wanted to sell the BM869 but they will not sell it to me.

Hello Dave,
Thank you for the explaination !
So, today I have received my BM789 but...
Really disappointed  :'(

It has the LCD washed out problem, as you show on your BM786 video.
I has also the right segments washed more than the other - exactly same problem as your video.

Tried with the new battery packed with, then new battery from me, then my Eneloop 100% fully charged: no screen change. (I use my Eneloop for my tests)
And slow auto-range (but this is not really a big problem).

Many great functions too..

No calibration certificate (whereas on BM257s ans BM869s it was there).
But no problem: it spots on with my 2 meters, even the U1272a who as a new certificate / 8 months old (I have recalibred my BM257s after). And my power supply has good calibration too (SPD3303X-E unlocked to X).
 
Compared to BM257s, BM869s and U1272A: the BM789 screen is really bad.
I have protection film on my meters too (original one on the U1272A  ;D , and one I have cut on my BM257s).

So I return the meter, I can't use a screen as bad as this one (I have mailed the shop to do that).

Also, I don't know if the rotary switch has some problem on the PCB tracks.

Some photos here (the BM869 is not there because not mine, but compared too)

The package (except Eneloop !) - not calibration certificate (strange from Brymen):
(http://morpheus.stigmata.free.fr/elec/BM789/20210603_215744.jpg)

The Screen  :(  :
(http://morpheus.stigmata.free.fr/elec/BM789/20210603_220038.jpg)

(http://morpheus.stigmata.free.fr/elec/BM789/20210603_220337.jpg)

(http://morpheus.stigmata.free.fr/elec/BM789/20210603_220500.jpg)



Is Brymen starting to fail? ???  :-\
Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on June 03, 2021, 11:17:32 pm
Brymen have never provided a calibration certificate  :-//
Perhaps they can offer one as an optional service to the supplier, but that would cost more.

As for autorange, I think it's quite quick, so  :-//
Title: Re: New EEVblog BM786 Multimeter
Post by: ceut on June 04, 2021, 12:07:44 am
Brymen have never provided a calibration certificate  :-//
Perhaps they can offer one as an optional service to the supplier, but that would cost more.

As for autorange, I think it's quite quick, so  :-//

Hello,
It's strange because I have had one with my 257s from them, and the serial number is matching with the back of my meter
 ???

Also, based on your photos, maybe the washed-out screen is something linked to the HY2613C Contrast setting which we can't change (there is a 10K resistor 01C R104 on pin 4 of it which is described as "VLCD" on the datasheet).
But I will not modify my meter to check that  :-\

For the auto-range: it is slower than my 2 others meters (257s and u1272a): I have seen that only when I checked the washed-out screen with all 3 meters in parallel, but I have no problem with that.

I think it is something with the 60.000 counts.

Edit: When I check a BM235 photo on this another great review
https://lygte-info.dk/review/DMMBrymen%20BM235%20UK.html
(https://lygte-info.dk/pic/Brymen/BM235/DSC_2988a.jpg)
=>the pin 4 of the same HY2613C chip is tied to a capacitor, so switch to "VLCD Internal Charge Pump" as they talk about on the datasheet with a recommanded value of 1uF.

Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on June 04, 2021, 12:16:00 am
I checked the one I have and indeed the contrast is so poor I can't make it out. 
Title: Re: New EEVblog BM786 Multimeter
Post by: Muttley Snickers on June 04, 2021, 02:23:13 am
I don't own this meter but was almost tempted after seeing the image below which was posted on the previous page  (https://www.eevblog.com/forum/testgear/new-eevblog-bm786-multimeter/msg3563827/#msg3563827)of this thread, the display appears to be quite crisp in contrast.   :-DMM


(https://i.imgur.com/KZOwOMQ.png)



Title: Re: New EEVblog BM786 Multimeter
Post by: EEVblog on June 04, 2021, 04:58:35 am
I don't own this meter but was almost tempted after seeing the image below which was posted on the previous page  (https://www.eevblog.com/forum/testgear/new-eevblog-bm786-multimeter/msg3563827/#msg3563827)of this thread, the display appears to be quite crisp in contrast.   :-DMM

(https://i.imgur.com/KZOwOMQ.png)

The contrast is good, but lighting and exposure makes a huge difference when doing comparisons.

BTW, I took this photo way back, not trying to show the LCD, just the sizes.
Title: Re: New EEVblog BM786 Multimeter
Post by: Cymaphore on June 04, 2021, 08:26:47 am
Is Brymen starting to fail? ???  :-\

I don't think so. First, by my personal impression, Brymen only recently got better with the displays. We've an old Beha-Amprobe Unitest Hexagon at the workplace, I'm certain it was built by Brymen. Horrible backlight, ok-ish LCD. Overall a good device.

Look at the amount of changes and innovations they do with every new product. With so many significant changes and improvements in relatively short time. They are not just building a box around some standard DMM-chipset with reference circuits, they are maintaining a line of ASICs. And at the same time a huge pressure in pricing and component part cost, no wonder they can't always get everything perfect.

Just look at the interior of that BM78x. You can really see that some engineers love what they are doing and trying to improve every spot available. With that amount of pressure, chances are higher that things go wrong or unexpected and you can't figure it all out before the things are boxed.

That kind of a gear with so much obvious engineering passion, functionality and quality in it and on it, for such a small price. I see no reason to be angry about imperfections or problems.
Title: Re: New EEVblog BM786 Multimeter
Post by: joeqsmith on June 04, 2021, 12:07:39 pm
The my 789 appears to have about the same contrast is the 786s.   Shown with the lab light, backlights on and outdoors.   Angle will make a big difference as well.  Sometimes when comparing so many meters, I have to tilt them just right to get a decent shot.   

https://youtu.be/pPCtnQa0Thc?t=979
Title: Re: New EEVblog BM786 Multimeter
Post by: Fungus on June 04, 2021, 12:56:10 pm
I don't understand why all these fancy meters aren't be as contrasty as a freebie DT830B.  What gives? :-//

(eg. are the freebies overdriving something so that the display won't last very long?)

Title: Re: New EEVblog BM786 Multimeter
Post by: HKJ on June 04, 2021, 01:23:25 pm
I don't understand why all these fancy meters aren't be as contrasty as a freebie DT830B.  What gives? :-//

(eg. are the freebies overdriving something so that the display won't last very long?)

When you have many segments on the display the contrast will be lower, due to the way they are scanned.