Returned Faulty BM235 Switch Investigation

[@bendavis1215]

Wow, surprised to see my multimeter on tv. I didn't open or scour the board fyi

[@psygn0sis]

(dun dun duuuun) The mystery deepens.

[@Blasterxp]

Thanks for clearing it up!

[@dnwheeler]

It looks like the unpopulated board was dropped on the floor at the factory and someone stepped on it, scraping up the surface.

[@KeanM]

If you didn't touch it, then it must have been the factory trying to address a related QC issue

[@Blitterbug]

@@KeanM Yeah, something dodgy there during assembly...

[@sanityd1]

I'd be interested in a video on your troubles with EU regulations.

[@Blasterxp]

Yes +1

[@RobertSzasz]

Tax stuff?

[@TheRcEngineer]

@@RobertSzasz Probably online return and warranty policies.

[@jca111]

@@TheRcEngineer and maybe compulsory disposal regulations?

[@tjsynkral]

@@TheRcEngineer He obviously stands behind the product so why would it be that?

[@redtails]

I can hear Louis Rossmann cry whenever you say "a small percentage of people"

[@rickt1866]

Louis Rossmann ch rocks i like when he gets into those what really grinds my gears rants lol

[@nighthawk8936]

literally the first thing I did when I heard "a small precentage of peope" was to hit the pause button and check in the comments if someone mentioned Apple or Rossman

[@MoraFermi]

As much as I like Louis, I really wish he realised that for Apple tens of thousands of affected devices can still be "a small percentage of" their entire production run. And maybe that somebody explained what a "selection bias" is to him.

[@bruceestrela]

@@MoraFermi Yes, i agree with that.

[@loeffel_hh]

To exclude the switch, you could test it with a top part and switch from another known good device, and of course test the switch/top part from this on the known good device

[@ikbendusan]

or solder wires to the lo-z position and then bend the board a little

[@illustriouschin]

Dave doesn't have time for that.

[@leonkernan]

agreed, wouldn't take long to swap the case over with another and see if the fault moves too.

[@sbaxter4207]

I thought he'd change the switch before taking time under a microscope looking for bad solder joints. or at least clean the contacts with an alcohol and swab.

[@tactileslut]

It's this sort of time that improves the product. I was glad to hear prior issues had been pushed to change orders.

[@nixxonnor]

It's nice that this video was posted, even though the mystery was not solved. To me it serves as a proof to that transparency and information is a good thing. The video made me even more confident that this is a good DMM and that EEVBlog is serious.

[@brianthompson1138]

I almost bought one of these and it's a great meter. But, I wanted separate AC/DC modes and bar graph, so I got a BM257s through TME, and I am very satisfied with that meter. So satisfied, that I made the 257s my work meter and bought a BM829s for home use. Totally satisfied with both of them. But, it was the BM835, your reviews and Joe Smith's testing that pointed me towards Brymen. It's always good to hear that they truly care about fixing issues and making a great product.

[@misturchips]

Good on ya, Dave - impartially disassembling your pride and joy without prejudice.

[@johnparkins9653]

Just what I was thinking

[@gabest4]

I know what DM6x is. They sold your board to FLIR. "FLIR DM64 HVAC TRMS Digital Multimeter with Temperatur"

[@nraynaud]

it's a rare case ... like a fluke?

[@Rickmakes]

nraynaud1 Comments don’t get much better than this.

[@gblargg]

A Bluke.

[@Blitterbug]

Ouch.

[@dj_paultuk7052]

Ha, you know i thought of that, then scrolled down and you beat me to it. lol

[@tjsynkral]

The only defective multimeter I've owned came from Fluke. kzbin.info/www/bejne/kGjNoYOYr8eEeKc (They fixed it up for me)

[@LiamTronix]

I wonder if it's a problem with the zebra strip to the LCD? That could explain the dropped segments when force is applied.

[@TheDefpom]

Check for cracked / low resistance surface mount capacitors, I see a lot of cracked/shorted caps. Also an idea to check those header jumper blocks to make sure they are clean and tight.

[@WacKEDmaN]

on the switch side there looks to be a scratched trace up near the power button...and some other "corrosion" looking area around one of the other button pads....maybe has something to do with the prob?

[@SidneyCritic]

Could the force on the range switch be flexing the PCB so the LCD breaks contact.

[@scottwolf9914]

DM62/DM66 appear to be FLIR multimeters with the same button/jack/switch layout as the BM235

[@ArlenMoulton2]

My Aneng An8008 did that after 6 months of daily use, not bad for such a cheap meter! I fixed it by using contact cleaner on the switch and applying new lithium grease.

[@derofromdown-under2832]

The lower part of the LCD membrane seems to have some glue on it... 10/10 Dave...

[@johncundiss9098]

My take on the whole thing that caught my eye was the added printing to the board. I bet dollar to a doughnut that meter has been cloned. Did it behind your back. Keep an eye out for the clone.

[@IIGrayfoxII]

The DM62, DM64, DM66 might be other multimeters and is used for ID purposes during manufacture Seeing as the 235 pad has some solder on it which corresponds to the model of this meter being a BM235 Edit DM62 is a Flir TRMS multimeter DM64 is a Flir HVAC mutlimeter DM661 is a Flir TRMS multimeter with VFD mode

[@lolvivo8783]

Do u mean Bryman is/was the assembler/manufacturer for above flir meters?

[@DrakkarCalethiel]

Hey dave, do you know if you can get a replacement LCD somewhere? My 235 did fall from quite some height and the LCD completely cracked. The Multimeter itself works still great, just the screen is gone.

[@idahocreator2491]

I would check the contacts for the lcd. The spring tension of the switch could be flexing pcb and breaking a connection on the lcd panel.

[@stevenspmd]

Just placed my order for a 2nd multimeter from Amazon.ca .. I compared Amazon.ca vs the EEVBlog store and the difference was not even $2 after exchange .. Hope, I went the right route to support Dave!

[@michaelwells8812]

DM62, DM64, DM66 are new handheld multimeters from FLIR. A quick search will find these products which seem to have the same specs, front panel layout, and lcd.

[@denisbaribeau509]

That unit was made either early Monday morning or late Friday afternoon.

[@juanabreu5127]

l´ve met many times that issue and always it is due to one or more steel ball coming off from its seat. The balls sit on top of springs between the selector knob and the upper cover to make the selection in a snap action way and assure good contact pressure.

[@lolvivo8783]

There is no steel ball here.

[@lmccleary411]

Put the board in a different case with different switch, it's probably a problem with the injection molded case not keeping the board in the right place/ pressure Plastic molding if very touchy and hard to keep thermal expansion / thermal warping under control at startup.

[@BaumInventions]

I have read "Returned Faulty BMW 325 Switch investigation" ... Facepalm for myself :D

[@Blasterxp]

Hahaha i wonder what car you drive!

[@BaumInventions]

@@Blasterxp Dacia Dokker :D

[@Blasterxp]

@@BaumInventions hihi okay, i totally didn't expect that lol

[@MrJef06]

Same here ;-)

[@TehGordonFreeman]

The DM62/64/66's are FLIR multimeters with what look like various specialisations for particular industry fields. Although the case design is aesthetically different, and it has a different LCD on it, they all appear functionally strikingly similar to this meter. I would put money on the same board being used in all the meters. Funny how the FLIR meters are more than twice the price though... Chalk it up to the magic sauce firmware I guess.

[@timothystevenson7907]

I did work for a training company getting test gear ready, half of the meeters came back with a similar fault, and once the battery was replaced it went away. Just a note as these symptoms are not necessarily a bad switch.

[@NICK-uy3nl]

I am surprised you, as a manufacturer, do not have a TEST FIXTURE where you plug the DVM board (through a test port) and test all functions and switch combinations automatically and generate a comprehensive 'health' report for the condition and calibrations of the DVM- and while testing you could apply pressure to different sections of the board to pinpoint possible mechanical issues. A programmable test station is a must for any self-respecting volume manufacturer

[@chocolate_squiggle]

As far as I remember, Dave doesn't manufacture any multimeters himself.

[@fan_Risk]

I believe that the interference is created by the movement of springs from batteries across the board. Perhaps there is some play and the springs are sliding along the board contacts. I'm surprised that such precision instruments use such unreliable connections.

[@thushararathnayake]

Hi Dave! Please tell me where to buy a replacement LCD panel for BM235. I have tried my best and it is not a connection problem. Some of the segments on the left-hand sides seem to be not coming on at all.

[@geovani60624]

You should have checked the souder joints, the board flex is clearly doing it, or maybe it's the way the display is mounted on tge board, the direction of the select is flexing the board just the right way to make the rubber connector lose connection

[@freethinker1492]

Dave I have a BM235 EEVblog meter and I have been very happy with it. But as you are always saying its always good to have 2 meters. I have been trying to get one of your 121GW meters from Amazon. But it says seller will not ship to canada is there a reason for this? I got my BM235 from Amazon no problem but I can't seem to get the 121GW

[@jdudb]

I would like to have seen some actual diagnosis of the problem, even if it was swapping cases or sub board with another meter or perhaps some comparison readings with another meter. I look forward to a followup.

[@stanburton6224]

Id try reflowing those resistors above and below the hole for the switch axle because of lead free solder cracking.

[@KrotowX]

I believe all BM2xx DMM line have similar design inside. Hope that my incoming BM257s will not have sanded contacts :)

[@diyelectronics5375]

Wornout plastic case maybe? Or wornout rotary switch? Or wornout PCB they loose contact.

[@MatthewSuffidy]

I'm a bit confused. Would it be accurate to say like meter 'A' malfunctioned: Board.A + Switch part.B = working? If this is the case that means the scratches on the board are not the problem. I would have said someone did something weird with it at the factory and there are some metal particles around the board. Some times I run into problems that go beyond empirical investigation, like the first CD burner I burnt I nearly took apart because the only bad batch of CD-Rs I ever purchased was the first one.

[@caulktel]

Hi Dave, my EEVblog branded BM-235 does not turn on some times when first switching the meter on, I just rotate the switch a few times and then it works okay, its done this from day one. Don’t know if it’s related or not.

[@andrewsweet43]

Same issue here. It turns on when i jiggle the switch...

[@youbecha64]

Surely you have a stack of those multimeters...can't you put a good board into that case/selector, and put the pictured board into a known good case/selector and see?

[@km5405]

my old holdpeak meter developped the same fault. i probably took it apart and rebuilt it like 6 times, but nothing .... the voltage and current mode also no longer made any sense at all. no clue why, no damaged solder joints atleast.

[@ewaldikemann4142]

It seems that Flir has some multimeters that look _very_ similar to this one: www.flir.com.au/products/dm66/, www.flir.com.au/products/dm64/, www.flir.com.au/products/dm62/

[@ForTheBirbs]

I got a Testo multimeter advert in the middle of the video.... ha!

[@swordofthelord7104]

So whats the best (cheapest!) way for people in Europe (Ireland actually!) to purchase your meters?

[@abeleski]

Wait for brexit

[@martinhodge921]

@@abeleski Brexit is a myth 😉

[@Gw0wvl]

@@martinhodge921 It is with all the crap these Backstabbing ReMOANERS are doing to try and stop it ... But it will happen , We will get there , Then we can legally import the meter 👍

[@Blitterbug]

@@abeleski After Brexit, we're all pretty much fucked anyways. Kissy byebye to piss-cheap Chinesium products on ebay, lads...

[@spehropefhany]

Come visit Canada or Australia, depending on whether you prefer to be frozen or fried.

[@MrAwyork]

I see something on the switch. On third from the inside track, there is much more ware then any other contact point. It looks like something on the video. I wish I could post a screenshot.

[@babylonfive]

You mean there's more wear?

[@MrAwyork]

@@babylonfive yeah, that word

[@Shim267]

I suspect the DM62 is referring to the FLIR DM62 in this case.

[@pcfxr4u]

Yo, Why don’t you try swapping your good meter contacts and/or boards? I’m surprised you didn’t already.

[@PatrickPoet]

Did you check the components for proper smoke quantity?

[@3v1Bunny]

@EEvblog2 might be interesting if this thing is gonna be scrapped to solder the bridges to put it in lo-z and bend the board .... still want to know if it is board compliance failing or the pressure of the contacts .. it is always so damn hard to find the smoking gun even in seemingly reproducible errors.

[@lasersbee]

2:41.. just checked mine and its an old "C" version as well. How do I upgrade to the newer version Dave ???

[@rofo88]

Buy a new one

[@lasersbee]

@@rofo88.. That's an expensive way to upgrade firmware.....:-\

[@mixerfistit5522]

@@lasersbee it's a model revision not a firmware version. There'll likely be physical changes internally.

[@lasersbee]

@@mixerfistit5522 Perhaps... Not going to buy a new model just to see if you are correct. If needed I'll probably get a Fluke.

[@mixerfistit5522]

@@lasersbee sorry, I didn't mean it in a way to suggest you needed to buy a new one. Hardware revisions don't necessarily add anything for the consumer/user. There's likely subtle redesigns in how the board is layed out, maybe a slightly different rated component to improve reliability (where the issue is so small it doesn't warrant a compete recall), they may even have just found a cheaper way to construct the unit. In some cases, and I'm not suggesting this isone, a newer revision can be inferior to an older model. Remember PS3 phats? 60GB = 4 usb ports, backwards compatibility with PS2 Replaced by 40 GB = 2 USB ports no backwards compatibility and internally a bit different. Cheaper to build, bit cheaper to sell

[@HotshotTopharley]

The Battery spring contact is faulty, clean and increase preassure should fix it.

[@paulkerr2298]

i love my BM235, worth every penny

[@andymouse]

We are trying to get out of the bloody EU (ya can tell how I voted) If I can show that dave wont sell his stuff in England because of EU problems this gives me ammo to get bloody BREXIT done..please tell your issues, if there not to personal.

[@spehropefhany]

I think they're getting hit in the crossfire between regulators and the makers of the dodgy-ist crap products (chargers, children's products, laser pointers, things that contact skin etc.). There have been more than 100 house fires in the NL alone because of crappy electronics and the EU folks have decided to move on it.

[@electronite7934]

You do NOT put vias on the path of the sliders!

[@spikester]

You still have the cheapest but highest quality unit with a true LoZ mode... my Fluke 289 is the only meter I have with that. Not even the 87V with its ridiculous pricetag has LoZ. Not surprise you sell thousands. :)

[@scottgibson7534]

£117.71 + £4.48 Delivery On amazon.. From Brymen direct inclusive of tax is £75.60 So thats £ 42.11 for a name.

[@dieboodskapper]

Plastic selector molded assembly might have warped.....try with known working assembly I would do....

[@exorbis9880]

As an unfortunate EU citizen, how can I order a BM235 multimeter without paying crazy shipping cost and/or waiting a month for it to arrive ?

[@bentumbentum]

www.welectron.com/Handmultimeter

[@stargazer7644]

What? LoZ mode is not for detecting ghost voltage. It's for avoiding it.

[@rodrigomaero]

Heck I hoped you would solve the issue

[@Gt403cyl]

While watching this video I was trying it and mine is actually doing the same thing, put it on v and it shut off by tweaking the switch. it only did it once but the dropping segments still happens.

[@wallacebrown3151]

Why not put the board in a good known unit and see if the problem follows the board?

[@deelkar]

L12 looks a bit dodgy, doesn't it? Also the triple via near the silkscreen for F1. Board looked deformed on the other side.

[@kevincozens6837]

Now I'm wondering about the difference between Rev. C and Rev. 9. I have one of each.

[@mrlithium69]

TLDR: he found nothing

[@NurdRage777]

Broken traces in PCB. Try flexing the board and see what happens !

[@deathcube2006]

try a new selector, and a different case. If problem persists, then it's a board issue, probably flex issue. I thought you would diagnose it lool

[@4youian]

Cool, thanks Dave

[@johnnythefixer]

7:08 min in. SW6 looks like it has a bit of damage/corrosion by the track ?

[@antoineroquentin2297]

Maybe a insulating liquid got on the PCB. (and someone tried to wipe it off)

[@adamsiwek7995]

No metal threaded inserts - I'm disapointed.

[@ferrumignis]

I'm a little surprised by that as well.

[@electrodacus]

Via's looks very strange on that PCB it is likely to be a bad PCB.

[@jburdman7]

Warning: Nothing is resolved here. It's 10 min of checking the selector contacts and giving up.

[@bcarm16]

Send it to me so I can have a go at seeing if its due to a dodgy via or something easy/tedious?

[@robertsistrunk6631]

4:55 "And I ooop"

[@Tigrou7777]

7:58 hidden BTC miner on the left, you are scamming us :)

[@tamaseduard5145]

nice 👍 🙏

[@whatthefunction9140]

I want one for Christmas

[@coreddit]

I would prefer one with a working range switch.

[@Blasterxp]

Me 2, i got an old one from conrad, its so slllloooooowwwww, even measuring a v9 battery gives 20 wrong valvues...

[@babylonfive]

Dave, keep going!

[@stampydragon2739]

Could you go find a ps3 and a ibm cell/be server card and draw ppl up a circuit board for a better single board computer I’m fed up with raspberry pi braking all the god darn time

[@imgertberg5344]

I miss the captioning in this video.

[@mohamadasriabdulazid4784]

Run those board in 5DX x-ray machine.

[@illustriouschin]

It could be one of those one-off things!!

[@ferrumignis]

More likely an on-off thing.

[@Flextro]

Lose captive screw with back cover...

[@HughMungoose]

The same thing just happened to mine! Nah just kidding haven't bought one yet, thought you could use the mini heart attack, lol!

[@rickt1866]

come on its a ready made product they just put your logo on it not a big deal

[@23RaySan]

looking forward for another 24h togglebot stream...im still sad because i missed cycle 75443

[@Drew-Dastardly]

Zebra strip?

[@dynorat12]

looks like too mush play in the knob

[@dani777dani]

bad design turn into useless device "david: cheap china dvm are bad" what about expensive garbage?

[@borayurt66]

I have my bet on a cracked multi cap.

[@radarmusen]

Flir DM64

[@MikeF1189]

swap cases

[@AlexTaradov]

Wait, what is going on here? This is a very old video.

[@cannesahs]

old?

[@AlexTaradov]

Yes, I remember watching this when BM235 was brand new.

[@AlexTaradov]

I guess I may be confusing it with this one kzbin.info/www/bejne/j36QXpauiZuLac0 , but really I feel like I already watched this specific video with this specific letter. May be a glitch in the matrix.

[@spehropefhany]

@@AlexTaradov If you smell burnt toast, time to call for the ambulance.

[@HDXFH]

EU is the new Soviet Union

[@Chupacabras222]

No, it is not. I used to live in socialistic block, and now I live in EU. Totally different worlds.

[@Chupacabras222]

@@goc9000 Populists (and commies) are popping out all around the Europe. It has NOTHING to do with principles of EU. And is not a valid argument to compare EU to Soviet Union.

[@Chupacabras222]

@Luca Capelli Why do you think EU is pure evil?

[@Blasterxp]

Well, some country tries to leave... More then 1 years so far.... Lol

[@Chupacabras222]

@@Blasterxp British representatives negotiated brexit agreement with EU TWICE. And they were unable to ratify it. Britain requested to postpone brexit several times. British politicians are the ones to blame. Not the EU, really. EU has no power to hold Britain. British promised to their voters heaven. They promised they will gain when they leave, which is nonsense. They cannot be in better position than member states. Leaving EU is dumb. EU has huge advantages and they will loose it. And thay doo not want to loose it, that's all. Brexit delays are about british polititions, not about EU.

[@elmin2323]

cheap and nasty