Author Topic: New EEVblog BM786 Multimeter  (Read 57313 times)

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Offline schwaggins

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Re: New EEVblog BM786 Multimeter
« Reply #375 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...
 

Offline EEVblog

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Re: New EEVblog BM786 Multimeter
« Reply #376 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.
 
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Offline Andrew McNamara

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Re: New EEVblog BM786 Multimeter
« Reply #377 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".  ;)
 
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Offline MK14

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Re: New EEVblog BM786 Multimeter
« Reply #378 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).
 

Online AVGresponding

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Re: New EEVblog BM786 Multimeter
« Reply #379 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...
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Offline MK14

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Re: New EEVblog BM786 Multimeter
« Reply #380 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.
 

Offline schwaggins

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Re: New EEVblog BM786 Multimeter
« Reply #381 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
 

Offline joeqsmith

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Re: New EEVblog BM786 Multimeter
« Reply #382 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.
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Offline MK14

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Re: New EEVblog BM786 Multimeter
« Reply #383 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.
 

Offline Fungus

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Re: New EEVblog BM786 Multimeter
« Reply #384 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.

 

Offline wizard69

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Re: New EEVblog BM786 Multimeter
« Reply #385 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.   
  • The continuity function works really nicely.   Nice loud buzzer and the flash of the back light is golden.
  • The test leads are not too bad for included with the meter.   I fear loosing the screw on parts almost immediately so will be looking for a small case of some sort for the meter and goodies.
  • My Petzl CORE rechargeable battery just doesn't fit.   I'm seriously thinking about seeing if can get the battery holder as a spare part to modify as it looks like I would just need to remove the battery separating lugs.   Or I could just use standard rechargeable batteries.   The Petzl is nice for the self contain charging feature,
  • While not an issue unique to this meter it wold be really nice if we could get a 3 digit mode when making AC measurements.   That is get rid of the fractional component and the other useless data.   The fact is all of those on screen digits are useless for a lot of "normal" AC work.   It doesn't matter to me if the line voltage is 120 or 120.34 VAC.
  • I've yet to read the manual!   That is a good thing as far as ease of use goes.   There are a couple of things I'm not yet clear on but most of my use so far has been on my back so no good bench time.   Overall though the meter really seems to be high quality

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.   
 
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Offline xvf22

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Re: New EEVblog BM786 Multimeter
« Reply #386 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?

 

Offline EEVblog

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Re: New EEVblog BM786 Multimeter
« Reply #387 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.
 

Offline Fungus

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Re: New EEVblog BM786 Multimeter
« Reply #388 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.

 

Online bdunham7

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Re: New EEVblog BM786 Multimeter
« Reply #389 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?
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

Offline Microdoser

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Re: New EEVblog BM786 Multimeter
« Reply #390 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
 

Offline EEVblog

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Re: New EEVblog BM786 Multimeter
« Reply #391 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.
 
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Offline wizard69

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Re: New EEVblog BM786 Multimeter
« Reply #392 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.
 

Offline NoisyBoy

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Re: New EEVblog BM786 Multimeter
« Reply #393 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.
 

Online bdunham7

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Re: New EEVblog BM786 Multimeter
« Reply #394 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.
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

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Re: New EEVblog BM786 Multimeter
« Reply #395 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.
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Offline IanB

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Re: New EEVblog BM786 Multimeter
« Reply #396 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.
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Online bdunham7

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Re: New EEVblog BM786 Multimeter
« Reply #397 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?
« Last Edit: March 27, 2021, 12:08:10 am by bdunham7 »
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

Offline NoisyBoy

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Re: New EEVblog BM786 Multimeter
« Reply #398 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.
 

Online rsjsouza

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Re: New EEVblog BM786 Multimeter
« Reply #399 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.
Vbe - vídeo blog eletrônico http://videos.vbeletronico.com

Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 


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