Author Topic: What do you think of your EEVblog Brymen BM235 Multimeter ?  (Read 55436 times)

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Offline joeqsmith

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #75 on: April 25, 2017, 04:39:25 pm »
I did write Brymen about the long settling times and provided them a link to the video.  Here is their response:

Quote
Hi Joe,

BM235 & BM869s firmware are with following reading smooth designs.


BM869s

After getting NEW measuring reading, check “NEW reading” and “the AVERAGE of the last 8 readings”.

If ABS ( “NEW reading” -  “the AVERAGE of the last 8 readings”) > 8 counts, then display “NEW reading” directly.

If ABS ( “NEW reading” -  “the AVERAGE of the last 8 readings”) <= 8 counts, then display “the AVERAGE of the last 8 readings” instead.

 

BM235

After getting NEW measuring reading, check “NEW reading” and “the AVERAGE of the last 16 readings”.

If ABS ( “NEW reading” -  “the AVERAGE of the last 16 readings”) > 16 counts, then display “NEW reading” directly.

If ABS ( “NEW reading” -  “the AVERAGE of the last 16 readings”) <= 16 counts, then display “the AVERAGE of the last 16 readings” instead.

They are the causes.

Offline IanB

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #76 on: April 25, 2017, 04:54:44 pm »
Interesting. I suspect they are trying to avoid "flickering" of the last digit if there is noise on the signal. The averaging approach will presumably give a more precise reading in such cases.
 

Offline Crumble

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #77 on: April 26, 2017, 09:22:04 am »
That's indeed interesting, I am sincerely surprised they actually pulled some code out of their database and provided it. :o It does mean a 150pF capacitor is actually a worst case scenario to test on a BM235 (but this averaging might be deactivated in capacitance mode). I guessed there would be a switch at about 20LSBs given the 220pF was quick while the 150pF was not, but this is the first time I hear a manufacturer provide such an detailed characterisation of such a behaviour. I applaud them for that! :clap: :-+

It does mean the BM235 takes 3,2s to settle after a small change (16 updates @ 0,2s/ud) and will trigger "fast mode" at 80counts/s. The 869s has the same update rate, so will apparently settle in 1,6s in normal mode (don't know if the same figure counts for hi-res mode) and will trigger at 40counts/s. Please note the 869s should be faster in responding to changes because it has higher resolution, so its 40counts/s will be equivalent to 4counts/s for a BM235 in most modes.

Thanks for checking that with the manufacturer, this is very interesting.

PS Averaging does not make the result more precise unless the meter has internal noise/jitter needing averaging, but it does not seem to be any more precise with averaging. It does help agains digit flickering, which is quite desirable and I don't mind the presence of the functionality. I like the values chosen for the 869s better though, and I'd have chosen the values for the 235 lower rather than higher to compensate for the lower resolution. Right now the 235 is powerless agains a multi-turn trimmer.  :-\

PS2 [nerd mode] I reread the "code", but it is not completely accurate. It obviously resets the average counter too after renewing the display value, else the value would jump to the correct one, but jump back when the average is back within 16 counts, this does not appear to happen.[/nerd mode]
 

Offline joeqsmith

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #78 on: April 27, 2017, 11:11:35 pm »
Please read the following from Brymen:

Quote
Hi Joe,
I had two wrong info. Please see red corrections below.
Best Regards,

BM869s
After getting NEW measuring reading, check “NEW reading” and “the AVERAGE of the last 8 readings”.
If ABS ( “NEW reading” -  “the AVERAGE of the last 8 readings”) > 16 counts, then display “NEW reading” directly.
If ABS ( “NEW reading” -  “the AVERAGE of the last 8 readings”) <= 16 counts, then display “the AVERAGE of the last 8 readings” instead.
 
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Offline EEVblog

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #79 on: April 28, 2017, 01:23:35 am »
I did write Brymen about the long settling times and provided them a link to the video.  Here is their response:

Quote
Hi Joe,

BM235 & BM869s firmware are with following reading smooth designs.


BM869s

After getting NEW measuring reading, check “NEW reading” and “the AVERAGE of the last 8 readings”.

If ABS ( “NEW reading” -  “the AVERAGE of the last 8 readings”) > 8 counts, then display “NEW reading” directly.

If ABS ( “NEW reading” -  “the AVERAGE of the last 8 readings”) <= 8 counts, then display “the AVERAGE of the last 8 readings” instead.

 

BM235

After getting NEW measuring reading, check “NEW reading” and “the AVERAGE of the last 16 readings”.

If ABS ( “NEW reading” -  “the AVERAGE of the last 16 readings”) > 16 counts, then display “NEW reading” directly.

If ABS ( “NEW reading” -  “the AVERAGE of the last 16 readings”) <= 16 counts, then display “the AVERAGE of the last 16 readings” instead.

They are the causes.

Cool, I've added that detail to the manual.
 
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Offline joeqsmith

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #80 on: April 28, 2017, 01:49:44 am »
Dave, if you decide to add the data for the BM869s as a reference, please make sure you use their corrections. 

Offline P90

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #81 on: April 28, 2017, 07:11:48 am »
Why do they even make meters that require shitty rubbish penlight batteries? They leak often, where as that's usually not the case with 9 volt batteries...
 

Offline djos

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #82 on: April 28, 2017, 07:21:09 am »
Why do they even make meters that require shitty rubbish penlight batteries? They leak often, where as that's usually not the case with 9 volt batteries...

Good question, I must admit I've found a number of leaking Duracell batteries lately in low power long life devices. It's quite concerning considering up till 6 months ago I'd never had issues with them.

Offline Crumble

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #83 on: April 28, 2017, 09:14:36 am »
Why do they even make meters that require shitty rubbish penlight batteries? They leak often, where as that's usually not the case with 9 volt batteries...
Good question, I must admit I've found a number of leaking Duracell batteries lately in low power long life devices. It's quite concerning considering up till 6 months ago I'd never had issues with them.
This seems to be a recent quality issue with Duracell batteries. I always regarded Duracell very highly, but their quality seems to have eroded. There is a video of bigclivedotcom showing 1) cheap alkalines outlasting them and 2) one of the types providing very inconsistent capacities. I usually recommend Varta's, but I have very little personal experience with capacity issues or leaking, so this is more to never having had a specific issue with them and it being a tracable brand. My thought would be that 9V would be just as prone to failure as other types.

I personally think a meter on penlights would be slightly more efficient, since a linear systems usually work on a modest range of voltages, and any excess will just cause more dissipation because bias currents usually stay the same (noting reality is rather more complicated). An AAA cell has more mAh's in it than a 9V cell, so a properly designed meter with AAA's could potentially outlast one on a 9V battery.
I did write Brymen about the long settling times and provided them a link to the video.  Here is their response:
Quote
[...]
Cool, I've added that detail to the manual.
Great!  :-+

I also found a video of mjlorton (27:40) noting there seems to be a settling time in AC measurements on the Amprobe rebadged BM857A. He also mentions here (40:36) when in manual mode it takes time to settle, but does not in auto mode, which is quite interesting and might or might not be related. I have not tried reproducing this (yet).
« Last Edit: May 16, 2017, 03:28:58 pm by Crumble »
 

Offline jordanp123

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #84 on: April 29, 2017, 12:37:53 am »
I must say I love my little Brymen 235. Until watching EEVBlog I had never heard of Brymen and I'm very surprised at the quality. I've got the 235 and a 869s now, I really like both of them. The silicon meter probes are superb, I've even ordered some spare ones for my fluke meters.
 

Offline jordanp123

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #85 on: May 05, 2017, 11:52:07 pm »
Speaking of which, looks like the EEVblog BM235 is out of stock on Amazon.com.
 

Offline joeqsmith

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #86 on: May 06, 2017, 12:09:54 am »
I must say I love my little Brymen 235. Until watching EEVBlog I had never heard of Brymen and I'm very surprised at the quality. I've got the 235 and a 869s now, I really like both of them. The silicon meter probes are superb, I've even ordered some spare ones for my fluke meters.

Welcome to the site.  I'm in the same boat.  I never heard of Brymen until a few years ago and also have the BM869s.  It gets a lot of use on the bench and it's my favorite meter by far.   


Offline tobor

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #87 on: May 10, 2017, 09:31:15 pm »
Love mine!  Only thing I miss is the bar graph at the bottom of the display, but I have other meters if I really need that for an application.
« Last Edit: May 10, 2017, 11:44:51 pm by tobor »
 

Offline HoracioDos

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #88 on: May 11, 2017, 12:42:53 pm »
I must say I love my little Brymen 235. Until watching EEVBlog I had never heard of Brymen and I'm very surprised at the quality. The silicon meter probes are superb, I've even ordered some spare ones for my fluke meters.

Welcome to the site.  I'm in the same boat.  I never heard of Brymen until a few years ago and also have the BM869s.  It gets a lot of use on the bench and it's my favorite meter by far.   

Almost the same here. Never heard of Brymen until I joined EEvBlog. I became a happy owner of a BM235, BM257S and a BM079 clamp meter this year. Since I started to buy better equipment I have the feeling I'm learning faster. Huge leap but I don't want to fool myself, they won't make me smarter.  :-DD
 

Offline boggis the cat

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #89 on: May 12, 2017, 05:36:14 am »
PS Averaging does not make the result more precise unless the meter has internal noise/jitter needing averaging, but it does not seem to be any more precise with averaging. It does help agains digit flickering, which is quite desirable and I don't mind the presence of the functionality. I like the values chosen for the 869s better though, and I'd have chosen the values for the 235 lower rather than higher to compensate for the lower resolution. Right now the 235 is powerless agains a multi-turn trimmer.  :-\
I think the logic here is that if you have a signal with a given amount of noise, the higher resolution meter will detect a significant change more often, so you want to average fewer points to retain more precision.

Given the available processing power in ASICs now, it surprises me that they don't have more in depth information available on demand.  Why not allow for the user to bring up not just the 'standard' minimum / maximum / average information, but additional statistical data?  A meter that is good at capturing spikes can deliver a less accurate picture of what is going on than one less capable, if it is stuck with min / max / avg.

Possibly this is not considered worthwhile because most applications requiring analysis of the signal quality would push the user to a 'scope, but it seems there is a gap in the market between 'standard' meters and data acquisition devices (or 'scopes used for that purpose).
 

Offline Crumble

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #90 on: May 16, 2017, 03:45:40 pm »
Why do they even make meters that require shitty rubbish penlight batteries? They leak often, where as that's usually not the case with 9 volt batteries...
Good question, I must admit I've found a number of leaking Duracell batteries lately in low power long life devices. It's quite concerning considering up till 6 months ago I'd never had issues with them.
This seems to be a recent quality issue with Duracell batteries. I always regarded Duracell very highly, but their quality seems to have eroded. There is a video of bigclivedotcom showing 1) cheap alkalines outlasting them and 2) one of the types providing very inconsistent capacities. I usually recommend Varta's, but I have very little personal experience with capacity issues or leaking, so this is more to never having had a specific issue with them and it being a tracable brand. My thought would be that 9V would be just as prone to failure as other types.
I noticed my stack of old batteries and found 2 (out of 4) Duracells (the industrial type) to leak when empty, while none of the other alkaline cells did. They had 2 and 3 years left in their expriration dates. These batteries came out of clocks and the likes, and were stored in locations without any significant environmental influences for less than a year. If your piece of equipment is prone to being stored long enough for the batteries to go flat I recommend you not use these! (Especially not on your pretty new BM235). It looks like it leaks from the bottom, but it is hard to tell. The top cap is near impossible to remove and I didn't bother.


PS Averaging does not make the result more precise unless the meter has internal noise/jitter needing averaging, but it does not seem to be any more precise with averaging. It does help agains digit flickering, which is quite desirable and I don't mind the presence of the functionality. I like the values chosen for the 869s better though, and I'd have chosen the values for the 235 lower rather than higher to compensate for the lower resolution. Right now the 235 is powerless agains a multi-turn trimmer.  :-\
I think the logic here is that if you have a signal with a given amount of noise, the higher resolution meter will detect a significant change more often, so you want to average fewer points to retain more precision.

[...]

Possibly this is not considered worthwhile because most applications requiring analysis of the signal quality would push the user to a 'scope, but it seems there is a gap in the market between 'standard' meters and data acquisition devices (or 'scopes used for that purpose).
My main point is if you want to tweak a circuit (let's say quiescent current settings or hysteresis tweaking) you'd rather have something that responds relatively quickly when doing a change. If I tweak a pot I want the result to display on my meter now instead of in 3,2s. I was recently experimenting and I used another meter for the purpose. When using the BM869 the tweak is way more likely to change enough counts to exceed the threshold than on the 235. As a matter of pure coincidence I was recently checking the linearity of a number of cheap multi-turn pots, measuring it every 30 degrees of rotation and I can tell you waiting for 3,2s for every measument is quite tedious. I used the Metrahit One for the second one because it takes just one screen update to show the final value.

On the other hand I must re-emphasise the info Brymen released did help a lot, now I at least know the value is correct after 3,2s rather than waiting for a random time period hoping it is settled then. With this kind of info I can make way more confident measurements.
« Last Edit: May 16, 2017, 04:53:29 pm by Crumble »
 

Offline Russ

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #91 on: November 18, 2017, 04:19:59 am »
Duracell’s are known to leak. They are crap. My EEVBlog meter arrived a few hours ago. I immediately dropped rechargeable Eneloops into it. I am liking this meter. I purchased it from Amazon. Getting it on Amazon, does Dave still make a few bucks on my purchase?

Russ
« Last Edit: November 18, 2017, 06:05:49 am by Russ »
 

Offline floobydust

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #92 on: November 18, 2017, 05:12:39 am »
Duracell batteries are absolute shit now. Here's one that isn't even dead!
Warren Buffett Berkshire Hathaway bought Procter & Gamble Co’s Duracell battery unit and lately they are cheap garbage.

Anyhow, Eneloops are great I love them.
 

Offline EEVblog

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #93 on: November 18, 2017, 07:05:35 am »
I purchased it from Amazon. Getting it on Amazon, does Dave still make a few bucks on my purchase?

More than few bucks. I am the one actually selling it on Amazon, I ship the stock to Amazon myself, all profits (minus Amazon's 18% FBA fee) go to me directly.
 

Offline kulla

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #94 on: November 18, 2017, 11:08:09 am »
I bought mine directly from https://www.eevblog.com/store with express DHL shipping to Sweden, $50 cheaper than Amazon with their fees  :wtf:
 

Offline Russ

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #95 on: November 18, 2017, 02:31:24 pm »
Dave

   Good to hear that you made a few $ on it. At $125.00, I think it’s a good deal. I immediately removed the Toshiba batteries and replaced them with Eneloops. Do the Toshiba’s have any known quality issues? I also purchased the carrying case too. 👍

Thanks
Russ
 

Offline djos

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #96 on: November 18, 2017, 09:47:40 pm »
Duracell batteries are absolute shit now. Here's one that isn't even dead!
Warren Buffett Berkshire Hathaway bought Procter & Gamble Co’s Duracell battery unit and lately they are cheap garbage.

Anyhow, Eneloops are great I love them.

Yeah I've found the same and as a result I buy the Aldi alkaline batteries now and have had zero issues in the last 6 months.

Offline Valden

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #97 on: July 13, 2018, 11:21:36 pm »
I have a question on the minimum capacitance measurements possible with the Brymen BM235, as well as the BM869S. Their specs state 20nF and 50nF respectively (IIRC), but I think these numbers reflect the highest measurement possible using the lowest range. What are the actual lowest measurements for capacitance? Has anyone checked?

Thanks. Rick.
 

Offline bc888

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #98 on: July 16, 2018, 10:38:03 pm »



Picked up the EEVblog BM235 and I'm at work trying to read up on it. I have not even powered it up yet and see the Duracell battery issue on this thread. Strange in that my daughter pointed out just the other day that my entire package of relatively new Duracell battery's were corroding while still in the package! Fortunately it was a Costco buy and they'll take them back. I've been using Enloops as well but I think I've got them loaded up in various toys and need to buy some more.
 

Offline Russ

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Re: What do you think of your EEVblog Brymen BM235 Multimeter ?
« Reply #99 on: July 17, 2018, 12:03:22 am »
The IKEA Ladda rechargeable batteries are actually, rebadged Eneloop Pro batteries. And much cheaper than the Eneloop branded versions. 👍
 The IKEA Ladda AAA batt’s are 900 mAh batteries.
 
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