EEVBlog branded Brymen BM235 in depth feature review and thoughts - Page 1
Forum section: electronics / testgear

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 21, 2016, 11:37:22 am
content: I know this is a long video but I really did test everything except the diode tester. Somehow I forgot about that. Being my first Brymen I'm impressed with the acuracy even down to the mV and uA.If you want to cut to the chase then the beginning is my thoughts. The middle is all testing, the end is a neat design feature I missed until I was cleaning up and my final thoughts over all. I don't normally review DMM's but being my first Brymen I thought I would run it through the ringer and fully test it. So I decided to video it also.FYI, I think I found the chase of the backlight noise also. I'll update once I'm done looking into it.UPDATE: This is the post with the tear down.https://www.eevblog.com/forum/testgear/quick-tear-down-of-the-eevblog-brymen-bm235-backlight-noise-research/https://youtu.be/sfXiTFebXlU

author: Fungus
author_rank: Super Contributor
timestamp: February 21, 2016, 12:02:01 pm
content: "Wringer". You put things through the "wringer"...This is a wringer:This is a ringer:

author: Brumby
author_rank: Unknown
timestamp: February 21, 2016, 12:14:18 pm
content: ... when auto correct won't help you, someone will always notice.

author: HAL-42b
author_rank: Frequent Contributor
timestamp: February 21, 2016, 12:17:33 pm
content: I didn't know about the blinky continuity feature. Nice!My only problem is that contrary to Dave I don't really like latched continuity. Most of the time I'm using that for checking worn cables with intermittent connection. For that application the cheap non-latched buzzer is best. You connect your leads and bend the cables and listen for the scratches. If the buzzer is latching type you can't do that.

author: EEVblog
author_rank: Unknown
timestamp: February 21, 2016, 12:19:57 pm
content: Cool, first review, thanks.

author: Bob F.
author_rank: Regular Contributor
timestamp: February 21, 2016, 12:44:07 pm
content: "Wringer" is correct... To put though harsh and excessive punishment or interrogation.

author: nctnico
author_rank: Super Contributor
timestamp: February 21, 2016, 12:56:31 pm
content: Quote from: HAL-42b on February 21, 2016, 12:17:33 pmI agree. Sometimes I have to do some reverse engineering and have to figure out which signal goes where on several chips with hundred pins or more each. Instant continuity test allows to drag the probe along the pins quickly and test hundreds of connections in seconds.

author: Wytnucls
author_rank: Super Contributor
timestamp: February 21, 2016, 01:43:58 pm
content: Transients below 100mS become difficult to hear. For instance, at 10mS, a 15dB sound pressure increase is necessary to detect a click at the same loudness as a 1 sec beep.A properly implemented latching continuity tester will circumvent this adverse effect.The Fluke 87V and 289 will pick up a transient of 1mS. The Fluke 179, 250uS.Ref: Master Handbook of Acoustics

author: HAL-42b
author_rank: Frequent Contributor
timestamp: February 21, 2016, 02:02:35 pm
content: I'm not listening for the beep. I have a continuous beep and I'm listening to an interruption or a scratch. If I hear a scratching noise while I'm wiggling the cable I know I have connection problems.So I'm listening for a dis-continuity, the exact thing a latching buzzer is trying to mask.

author: nctnico
author_rank: Super Contributor
timestamp: February 21, 2016, 02:10:26 pm
content: Quote from: Wytnucls on February 21, 2016, 01:43:58 pmBy that time I'll be 100 pins further. If the beep is difficult to hear I go slower over the pins to make the tone last longer; simple as that!

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 21, 2016, 02:39:40 pm
content: Quote from: EEVblog on February 21, 2016, 12:19:57 pmYour Welcome, it was fun to do.I needed to test out that process calibrator also. So I was able to get two things done in one shot.

author: lpc32
author_rank: Frequent Contributor
timestamp: February 21, 2016, 03:01:29 pm
content: Aren't there meters with toggleable latching?

author: Wytnucls
author_rank: Super Contributor
timestamp: February 21, 2016, 04:02:14 pm
content: If the two surrounding sounds are the same (spectra, duration), the auditory gap detection threshold (GDT) is 2-3mS. It increases to 20mS otherwise.Manufacturers don't specify in their datasheets if their multimeters can detect such a gap in a constant short circuit. It should be easy to find out, with the right equipment.(Hearing: An Introduction to Psychological and Physiological AcousticsBy Stanley A. Gelfand)https://books.google.mu/books?id=ZlnvBQAAQBAJ

author: Wytnucls
author_rank: Super Contributor
timestamp: February 21, 2016, 05:02:47 pm
content: As an example, this simulation of an intermittent connection (2-5mS) is detected by the Fluke 185 (latched continuity <1mS) as a single event, with a single beep interruption:(The Uni-T UT-71 series, with its notoriously slow latched continuity, doesn't detect this intermittent connection)

author: HAL-42b
author_rank: Frequent Contributor
timestamp: February 21, 2016, 05:22:57 pm
content: Quote from: Wytnucls on February 21, 2016, 05:02:47 pmInteresting. I wonder what the book says about tone acuity. If I was trying to improve the buzzer that would be the area I'd look into. Resistance controlled oscillator sensitive to 0-20 Ohms.We've completely hijacked the thread though, better take this to another thread.

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 21, 2016, 05:24:17 pm
content: As I mentioned in the main post. This is the update for the thread to the tear down video.https://www.eevblog.com/forum/testgear/quick-tear-down-of-the-eevblog-brymen-bm235-backlight-noise-research/

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 21, 2016, 05:27:47 pm
content: Quote from: HAL-42b on February 21, 2016, 05:22:57 pmLOL, it's not like anyone is replying to my post. Their just watching the video. At least your hijacking keeps the thread at the top for others to see.

author: Wytnucls
author_rank: Super Contributor
timestamp: February 21, 2016, 05:29:56 pm
content: Quote from: HAL-42b on February 21, 2016, 05:22:57 pmWell, this is still relevant to the latched continuity of the Brymen 235. Tone acuity is supposedly better as the frequency increases.

author: boggis the cat
author_rank: Regular Contributor
timestamp: February 23, 2016, 02:09:45 am
content: Just got the BM235 I ordered from Dave and it had a rattle. In my experience that doesn't bode well.Turns out it is a small jumper that was loose inside. The only jumper pins present are labelled "J1". Should these have a jumper in place, or did I get a free bonus from Brymen?I also noticed that there is a position on the main board for a LED that seems to be aligned with the comms port (holes are present in the rear case). I might check if there is any signal present across there, presuming it to be for a data send option.

author: MarvinTheMartian
author_rank: Frequent Contributor
timestamp: February 23, 2016, 03:36:27 am
content: Quote from: boggis the cat on February 23, 2016, 02:09:45 amJust cracked mine open - small plastic base on the jumper pins but no jumper in place. You've scored yourself a spare jumper.No idea what the jumper is for though

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 23, 2016, 04:34:47 am
content: Quote from: boggis the cat on February 23, 2016, 02:09:45 amI've already done a tear down, that jumper on J1 should be empty.So keep the jumper and call it a bonus.

author: boggis the cat
author_rank: Regular Contributor
timestamp: February 23, 2016, 05:02:16 am
content: Quote from: Scottjd on February 23, 2016, 04:34:47 amOK, thanks.My guess is that 'J1' would be for calibration adjustment, but I'm not too keen on experimenting and discovering that is does something else, like zeroing out the calibration data.

author: crispy_tofu
author_rank: Super Contributor
timestamp: February 23, 2016, 06:19:15 am
content: Thanks for the review!

author: MarvinTheMartian
author_rank: Frequent Contributor
timestamp: February 23, 2016, 09:29:17 am
content: Does anyone actually know what the J1 jumper if for?

author: Johnny Electron
author_rank: Contributor
timestamp: February 28, 2016, 02:45:26 pm
content: Very well done review! Thanks for that!

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 28, 2016, 04:48:44 pm
content: Quote from: crispy_tofu on February 23, 2016, 06:19:15 amYour welcome.

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 28, 2016, 04:49:52 pm
content: Quote from: MarvinTheMartian on February 23, 2016, 09:29:17 amI skimmed the data sheet but didn't see it. But I also can't translate it, maybe you would have better luck.http://www.hycontek.com/attachments/LCD/DS-HY2613_TC.pdf

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 28, 2016, 04:50:59 pm
content: Quote from: Johnny Electron on February 28, 2016, 02:45:26 pmThanks, I'm glad you liked it..

author: Scottjd
author_rank: Frequent Contributor
timestamp: February 28, 2016, 05:23:23 pm
content: I tried something different to fix/lower the back light noise.Still really like this meter even when it had the back light noise.https://youtu.be/TfNuTmqtiD4

author: MarvinTheMartian
author_rank: Frequent Contributor
timestamp: February 29, 2016, 01:54:49 am
content: Quote from: Scottjd on February 28, 2016, 04:49:52 pmNo joy, I can't read Chinese either!

author: EEVblog
author_rank: Unknown
timestamp: March 03, 2016, 10:32:11 pm
content: Some very serious problems with the meter it seems!

author: RobertoLG
author_rank: Frequent Contributor
timestamp: March 03, 2016, 10:40:25 pm
content: Quote from: EEVblog on March 03, 2016, 10:32:11 pmya really serious, what a fail!!!1

author: Muttley Snickers
author_rank: Unknown
timestamp: March 03, 2016, 10:43:14 pm
content: As you well know Dave I was the first to get one but after seeing this video I might well be the first one to send it back, a complete and utter fail, getting some weird arse resistance readings on my mashed potatoes......

author: nidlaX
author_rank: Frequent Contributor
timestamp: March 03, 2016, 10:45:50 pm
content: Quote from: EEVblog on March 03, 2016, 10:32:11 pmA wise person once told me: it's not the length of the chopstick, but rather your finesse at manipulating wooden poles that matters.

author: EEVblog
author_rank: Unknown
timestamp: March 03, 2016, 10:48:05 pm
content: Got notification of my first returned unit from GermanySo much for that experiment, Germany off the list again.

author: Lightages
author_rank: Unknown
timestamp: March 03, 2016, 10:50:59 pm
content: Really? REALLY? That guy has no business doing multimeter reviews. What kind of nonsense is that. Probes for chopsticks? Can't we be serious about these things? This is someone's living, namely Dave's. Someone could watch this review and get sincerely concerned that the probes are too short for eating Chinese food.Really, it is obvious that the real problem is that the meter doesn't match his curtains. How can he live with that colour!?

author: hopski
author_rank: Regular Contributor
timestamp: March 03, 2016, 11:16:10 pm
content: Quote from: Lightages on March 03, 2016, 10:50:59 pmYeah. what was he thinkin? Chicken?! Everyone knows Dave's meter is vegetarian

author: mos6502
author_rank: Frequent Contributor
timestamp: March 03, 2016, 11:20:42 pm
content: Quote from: EEVblog on March 03, 2016, 10:48:05 pmI'm sure it was just a misunderstanding. The guy measured a 1k resistor and the display read NEIN NEIN NEIN.

author: Brumby
author_rank: Unknown
timestamp: March 03, 2016, 11:22:19 pm
content: Quote from: Lightages on March 03, 2016, 10:50:59 pmThe box for the BM235 seemed to go well with his curtains........

author: RobertoLG
author_rank: Frequent Contributor
timestamp: March 03, 2016, 11:23:04 pm
content: see, dave tought he would get away with it, and he doesn't ship any sauce with it too, complete fail...

author: Scottjd
author_rank: Frequent Contributor
timestamp: March 04, 2016, 12:05:47 am
content: Quote from: hopski on March 03, 2016, 11:16:10 pmAhh, that was my problem. I didn't know Dave meter is vegetarian. No wonder it didn't give acurate readings with my steaks.

author: nidlaX
author_rank: Frequent Contributor
timestamp: March 04, 2016, 12:28:26 am
content: Quote from: Scottjd on March 04, 2016, 12:05:47 amI did a stovetop sous vide of some filet minon the other day. Used my UT71B instead of my BM257s because the Brymen only resolves down to 1 degree F and didn't come with the RS232 kit (how was I supposed to monitor my steak through remote desktop while working upstairs?). What a let down.

author: Brumby
author_rank: Unknown
timestamp: March 04, 2016, 12:29:52 am
content: I tried it with sausages and lamb chops. It seemed to do better with the sausages, but overall it wasn't much chop.

author: sleary78
author_rank: Unknown
timestamp: March 06, 2016, 12:19:43 pm
content: Hey.. i finally got round to adding the flame effect ...And yes... My curtains are terrible (came with the house, honest guv) and I wince every time i see them. I'm hoping that a public display of them will make the wife find me new ones

author: sleary78
author_rank: Unknown
timestamp: March 06, 2016, 01:01:31 pm
content: Quote from: Lightages on March 03, 2016, 10:50:59 pmYou've obviously never seen Micro Men thenEDIT: Its my kind of nonsense and I gave Dave a veto before publishing it. Which BTW still stands if he ever wants me to remove it.

author: SeanB
author_rank: Super Contributor
timestamp: March 06, 2016, 02:02:25 pm
content: Quote from: sleary78 on March 06, 2016, 12:19:43 pmYou do know that they can be removed from the wall without tools other than some household steps.........

author: sleary78
author_rank: Unknown
timestamp: March 06, 2016, 02:22:04 pm
content: Quote from: SeanB on March 06, 2016, 02:02:25 pmbut unfortunately the sun comes through that window while im working and blinds me (when it decides to appear in Scotland). Trust me i'd burn them in spectacular fashion if i didn't need them. I might steal the spare set of blackout blinds from my kids room and use them instead.

author: mos6502
author_rank: Frequent Contributor
timestamp: March 13, 2016, 04:50:18 pm
content: So ... do you wanna get rid of that Amiga 2000 and 3000?I can give you some excellent curtains in exchange.

author: sleary78
author_rank: Unknown
timestamp: March 15, 2016, 06:41:46 pm
content: Quote from: mos6502 on March 13, 2016, 04:50:18 pmHah! Its an Amiga 4000 (I might consider parting with that) and an A540 with an original FPA (Will never part with that.. super rare)