Electronics Repair Is Hard Enough Already - Don't Make This Stupid Mistake And Make It Worse!

No video

Electronics Repair Is Hard Enough Already - Don't Make This Stupid Mistake And Make It Worse!

Рет қаралды 26,281

Күн бұрын

This mistake could cost you a lot of wasted time and effort - and may prevent you from completing a repair successfully. Watch this video to make sure it doesn't happen to you.
I work in collaboration with:
The Electronics Channel (live streams with Carlos and Detlef)
/ @theelectronicschannel
Gran Canaria Uncovered
/ @grancanariauncovered (with Detlef and Julie. Not electronics related)
Det Builds Stuff - / @detbuildsstuff (Detlef)
Retro Upgrade - / @retroupgrade (Carlos)
For All Your PCB needs: free $5 discount coupon
www.pcbway.com...
Equipment used in my videos. These are affiliate links, you pay the normal price and I make a small commission.
TEST METERS
ANENG AN8009 MULITIMETER
s.click.aliexp...
amzn.to/4da4Q7h
amzn.to/4fsjkkm
amzn.to/3yuf03q
amzn.to/4fwQOOD
www.banggood.c...
KAIWEETS HT118E MULTIMETER
s.click.aliexp...
amzn.to/3yC0ZRe
amzn.to/3SHIEcy
www.banggood.c...
VC480C+ MILLIOHM METER
s.click.aliexp...
amzn.to/46Gg1Cm
amzn.to/3YwUjyn
MESR-100 ESR METER
amzn.to/3yxQ0Zd
amzn.to/3WSr73A
s.click.aliexp...
XC6013L CAPACITOR METER
s.click.aliexp...
amzn.to/4cf2lzm
amzn.to/4dw9cp5
TM-902C TEMPERATURE METER
s.click.aliexp...
amzn.to/4fAz44L
amzn.to/4fBxD69
LCR-T4 COMPONENT ANALYZER
s.click.aliexp...
www.banggood.c...
amzn.to/3X4rOHv
amzn.to/3Agcj6h
FNB58 USB ANALYZER
s.click.aliexp...
amzn.to/3MgBFnn
amzn.to/4dyLU1H
www.banggood.c...
PCI POST ANALYZER
s.click.aliexp...
amzn.to/4dd8ihw
amzn.to/3LTpeO7
TL460S PLUS PCI_E ANALYZER
s.click.aliexp...
amzn.to/3WEsdi6
TOOLTOP ET120MC2 SCOPE
s.click.aliexp...
amzn.to/4dCaz5L
amzn.to/4dxOYLt
FNIRSI 1014D SCOPE
s.click.aliexp...
amzn.to/3AdZqK1
www.banggood.c...
NPS3010W 30V 10A PSU
s.click.aliexp...
amzn.to/4dzl2yM
T12 STATION WITH M8 9501 HANDLE
s.click.aliexp...
amzn.to/46E73W6
M8 9501 HANDLE
s.click.aliexp...
YIHUA 982 Soldering Station C210/C245
s.click.aliexp...
FNIRSI HS-02 PORTABLE SOLDERING C210/C245
s.click.aliexp...
amzn.to/3Yv7Ma5
QUICK 861DW
s.click.aliexp...
amzn.to/3WDF4B5
amzn.to/4ci7rdW
PROS'KIT SS-331H
s.click.aliexp...
INFIRAY P2 PRO IR CAMERA + MACRO LENS
s.click.aliexp...
www.banggood.c...
amzn.to/4coSRle
amzn.to/4coSV4s
TOOLTOP ET13S THERMAL CAMERA METER
s.click.aliexp...
ET13S MACRO LENS
s.click.aliexp...
OPTICAL MICROSCOPE
s.click.aliexp...
usa.banggood.c...
amzn.to/4dzBA9G
TOMLOV TM4K AF FLEX
amzn.to/3LY0YKs
tomlov.com/pro...
TL866 II+ PROGRAMMER
s.click.aliexp...
amzn.to/3SGKL05
CH341 PROGRAMMER
s.click.aliexp...
NC-559-ASM FLUX
s.click.aliexp...
DESOLDER BRAID (I use size 8045)
s.click.aliexp...
s.click.aliexp...
HX-T100 SOLDER (0.6MM)
s.click.aliexp...
ESD-11 TWEEZERS
s.click.aliexp...
Learn Electronics Repair is now on Discord! Come and join the fun, it's free.
/ discord
If you would like to support this channel
You can send donations
www.paypal.com...
You can subscribe to Patreon
/ learnelectronicsrepair
You can click Join to become a channel member
Thank you
Richard

Пікірлер: 110

@bobapthorpe Жыл бұрын

I hit this exact situation during an electronics lab session in college. Took two of us over an hour to sort out why we were seeing microvolt signals on the scope while the LED on our logic probe was lighting up. We changed out everything in the circuit and were at the point of swapping out the scope when the probe cable sheared off leaving only the connector on the scope. Absolutely infuriating BUT provided a lifelong lesson to never trust cables and connectors, especially those that are constantly beat up in a electronics lab classroom.

@deangriffiths8107 2 жыл бұрын

If you’re not making mistakes it’s because you’ve never done anything.

@LearnElectronicsRepair 2 жыл бұрын

very true 😉

@bosborn1 2 жыл бұрын

Yep, there was only one dude who never made mistakes, and we crucified that guy. (Said as a joke, not a religious statement)

@Str8Reckless63 Жыл бұрын

@@bosborn1 oh snap, that’s a good one though. Love the humor

@MrMaxeemum 2 жыл бұрын

Happens to the best of us. Should probably try to get in the habit of probing the calibration point on the front of the scope occasionally. It'll be interesting to see the difference with the HDMI job.

@danriches7328 2 жыл бұрын

I got into this habit in my first job and it's saved me a ton of time over the years and meant I can trust what I'm seeing just a little bit more. Nicely pointed out by the way!!

@LearnElectronicsRepair 2 жыл бұрын

asolutely - it's not like I didn't know or wasn't taught to do these things - just sometimes standards slip due to over-familiarity and the fact that almost always the scope/meter whatever probe is fine

@royalaxe 2 жыл бұрын

guys, i would rather trust a battery to test from, its isolated from bad AC input.. or the multimeter might be at fault as well.

@gdj6298 2 жыл бұрын

But if the problem is in the GROUND connection to the probe - won't the calibration point still read good, if it's grounded internally ?

@danriches7328 2 жыл бұрын

@@gdj6298 not necessarily as you'll see a ton of noise on the scope, this is down to the electron propagation needing a return path which is as close as possible to the signal wire. You can try this yourself by grounding the ground lead and removing it whilst looking at the scope. Once you get used to the difference you'll notice of there's a missing ground straight away, it's really down to years of experience and checking three times. I didn't realise this when learning all those years ago and wasn't really told why. It's definitely a good thing to question everything all the time though, as you'll make less mistakes and learn a lot. Have fun electronicing!!

@ThePetaaaaa 2 жыл бұрын

Been there, done that! No flag from my side! I’ve experienced more bad probes than I can count. At some point they break, especially if you misuse them mechanically or in a climate chamber… I like to have a 1.5 V battery handy to check my scope or voltmeter. P.S. Keep the wire and BNC connector of the dead probes! It’s a special kind of lossy coax and quite hard or even impossible to come by.

@Paddijaddi 2 жыл бұрын

Ive got semi-related experience: Im working in test development, so i'm developing/maintaining testequipment for our products. Basically I build adapters that connect testequipment (multimeters, sources, loads etc.) to the devices under test (ranges from simple pcbs to multi-pcb modules to full devices). Maintaining in my case means, everytime there is a problem with my adapter, someone calls me to fix it. 95% of the time its the cables. Either shorted inside, or the soldered connection broke off, the crimping got old, someone plugged it in the wrong way... there is a surprising amount of ways a cable/connection can be the reason for a fault. So if youre ever working on some elaborate setup and its giving surprising results: Check your cables. Especially if you frequently (un)plug them.

@GiNodrog 2 жыл бұрын

That's what the 5v square wave test point is for on the scope "most scopes have one". I used to tell my students to always test that first , (also this test point is their to calibrate the probs "little preset on the probe").

@c4b0ombazzist90 2 жыл бұрын

Humility... So refreshing these days.

@StationGarageSt Жыл бұрын

No chastising needed, just plenty of praise for your scientific honesty!

@andymouse 2 жыл бұрын

Nice one ! I always tap the ' calibration ' output on the scope with my probe as a sanity check !.....cheers.

@electronash 2 жыл бұрын

Hey, I was gonna say that! Allo, Andy. lol

@electronash 2 жыл бұрын

I had a similar issue with my Rigol o'scope about six months ago (same model as in this vid), I wasn't getting proper readings with it. Turned out the stupid end piece of the probe was loose, and had a tiny gap between the two parts. lol

@andymouse 2 жыл бұрын

@@electronash Watcha !

@electronash 2 жыл бұрын

@@andymouse I found a neat use for the 1 KHz test output on the o'scopes, btw... A couple of years ago, I needed to reverse engineer the pinout of an FPGA vs the other chips (RAM etc.) on a board. Originally, I was going to just use a counter on the FPGA to output a bit to each pin, then use the frequency to figure out which pin was used. But that could cause possible contention. So instead, I just added ALL the pins to a SignalTap instance, and set them all as inputs. Then used a resistor from the o'scope's 1 KHz test output to probe each trace. There was a small amount of crosstalk on adjacent traces, but it was still obvious which pin was the correct one. I managed to reverse about 95% of the pin mapping that way. I don't own a proper signal gen. lol

@andymouse 2 жыл бұрын

@@electronash Nice application and good thinking ! that would be a good video for someone to make, highlighting odd ways to use the 1Khz cal output !! cheers!

@Johadart 2 жыл бұрын

Richard we all been down that road, I had a jinky feeling it may of been your test lead, but you got into it great, cheers bud keep up the great work mate 🤙🏼🇦🇺

@gregbennett2437 Жыл бұрын

Knowledge from a mistake is not easily forgotten. Thanks for sharing.

@CXensation 2 жыл бұрын

Classic. Been there - several times. Looking forward to a review on the HDMI problem tracing 👍

@jeisonsanchez4842 2 жыл бұрын

I always learn from your mistakes. Thanks to your previous two HDMI videos, these connectors are less of a mystery. I appreciate the in depth explanations and the demonstration of using an oscilloscope (for HDMI and the AM/FM radio repair). I also like the 1hr+ videos and don’t mind the multimeter continuity beeps lol.

@LearnElectronicsRepair 2 жыл бұрын

Thank you. Most of the info I publish is already 'out there' It's just sometimes hard to access and even harder to put together in a coherent way from the point of view of trying to fix stuff. I can't guarantee that learning this stuff will enable you to repair HDMI problems all the time but I can guarantee it will give you a logical method to go about it 😉

@CTCTraining1 2 жыл бұрын

Well worth sharing as a reminder. Does your scope come with a little function generator point on the front as a sanity check? Is that the quickest way to check you are good to go?

@LearnElectronicsRepair 2 жыл бұрын

Yes it has a square wave 'calibration' generator - I should remember to use it!

@DarrenHughes-Hybrid Жыл бұрын

Thank you for the great reminder! I have made these kinds of mistake and worse and will again, I'm sure, so thank you. Maybe your reminder will help me NOT make some mistakes I would have made, if you hadn't made me more careful.

@f1remandg 2 жыл бұрын

Excellent that you found the fault and realised that it was the tool, also credit to you, that you told every body. Full 5***** DG

@LearnElectronicsRepair 2 жыл бұрын

Well if there is one thing this channel is, it is real 😁

@tomluque Жыл бұрын

Thats why I always use the scope's 1V @ 1KHZ Calibration signal output to verify the probe & scope.

@doogsm6013 Жыл бұрын

Just went through testing a ton of components on an RCA VoltOhmyst WV-500B I picked up on ebay because non of the ranges were working consistently. Turns out the integral probe cable has an intermittent fault at the strain relief going into the meter. Trimmed it back and ready for calibration now. Bit of a D'oh moment.

@p1366 2 жыл бұрын

Brilliant! Thanks for sharing the fail, very important to show this kind of gotcha! I use the test signal point on my scope to "calibrate" before probing,,, too many times done the 1x/x10 mixup and the AC/DC coupling..Cheers!

@SomeGuyInSandy 2 жыл бұрын

Good point. I was using my Peak semiconductor tester to test a voltage regulator that may or may not have been bad. The tester told me that there was no component present. Checking the manual showed that it can only check VR's up to 8 volts! It's a great test tool, but I was using it incorrectly. Testing that same component with my multimeter proved that it was still ok.

@LousyPainter 2 жыл бұрын

Very good. Something lots of people have done. Including myself. Cheers.

@disklamer 2 жыл бұрын

I learned a lot about camera shake and seizure inducing strobing. That is, to avoid videos with those visually toxic features.

@AlaskanInsights 2 жыл бұрын

lol,, had a problem with my fluke multimeter... new leads and readings all over the place... ended up cutting off the insulation and the tips were not even soldered to the wires. just crimped and a bad crimp at that... messed with me for hours.

@ruimvp 2 жыл бұрын

It happen to me also with multimeter probes. But has the multimeter was new i try to activate the warranty. But they said that kind of material is like a consumable and not covered by warranty. I was young then and accepted.

@royalaxe 2 жыл бұрын

weve all done this at some stage... trust nothing until tested at the start of a fault find.. when i was on a mine site i tested my multimeter religiously with a never touched 12v 6.5Ah alarm system battery which had one purpose only, to check the multimeter for 12vdc accuracy. many years ago electronics out of the box, brand spanking new you could trust as being perfect 99.99% of the time... then it seems, at least in the electronic security area, you would get components faulty from the factory, around 1%. then it went to 20% in 2001 or so... a sad statement on quality control worldwide..

@fernandobellido 2 жыл бұрын

Always useful to remember this

@romancharak3675 2 жыл бұрын

Ouch! Been there, done that too. So frustrating.

@Sicktrickintuner 2 жыл бұрын

Yep found that in automotive testing. Don’t assume the tools are good ever

@juliocesarpalma5199 Жыл бұрын

Thank you for sharing :)

@anesibs9487 2 жыл бұрын

Thanks for tip

@DracoMcGuyver 8 ай бұрын

Evey scope that I have ever seen has a 5 volt DC square wave output terminal for calibrating your probes. I always check before I measure.

@dalerobinsuk 2 жыл бұрын

Absolutely agree with this! I've has this exact issue with a Tektronix scope and Tektronix probes not long ago, spurious readings taking me up the garden path. These have a small connection that connects to the BNC part and it was not fully inserted... Another major issue is with RF/Coax patch leads. I've lost count of how many times I've been trying to repair or align a transceiver had had spurious power readings, high SWR and desensitised front ends. All because of an rf cable. I only buy high quality interconnects and coax cable now. And one important advice I can give anyone. If you're working with a HV/EHT probe, check at least 3 times you have the ground lead connected!!!

@LearnElectronicsRepair 2 жыл бұрын

Seeing as a HV/EHT probe is basically a voltage divider it would make sense to ensure one end of the resistor chain is connected to ground! Unless you want to become part of the voltage divider yourself😆

@dalerobinsuk 2 жыл бұрын

@@LearnElectronicsRepair Yes exactly😀that's why I said check 3 times. I have had the ground pop off while I was measuring the EHT on a CRT, that gave me a fright 😂

@opal177 2 жыл бұрын

Too late. 😁 Been there. Done it. Thank you for your amazing lessons.

@KD0CAC 2 жыл бұрын

Test your tester , dash diving = working upside down looking for power under the dashboard of a car , could not find power , after a while I figured out the bulb was broken in the testlight ;)

@remu3881 2 жыл бұрын

Very neat board 👌 👍 but do you need suitcase or backpack for the battery's 🤣😂

@Ghost572 2 жыл бұрын

This is a good lesson to learn actually, I wonder if there is a way to force your self to calibrate the probes every so often, like written into the scope its self, or just modify the scope to have something that monitors the last time the calibration button was pressed and then display it on a little display.

@zedcarr6128 2 жыл бұрын

I've been a professional service engineer for over 35 years and a hobbyist for well over 40 years, and I've NEVER done anything like that, EVER. I've never let the magic smoke out, never tried to measure voltages on something that isn't powered up, never connected a power supply the wrong way round, never inserted an electrolytic or tant the wrong way round, or any semiconductors whatsoever. 🔥🔥🔥🔥🔥🔥🔥🔥🔥🔥 🩲 🔥🔥🔥🔥🔥🔥🔥🔥🔥🔥

@LearnElectronicsRepair 2 жыл бұрын

Or tried to measure voltage with your multimeter (leads and all) set to AMPS! 😆

@dalerobinsuk 2 жыл бұрын

You haven't been doing it properly 😂

@hafidhmahmood5181 2 жыл бұрын

Ya, he has NEVER EVER done it properly 😄

@anndaly9381 2 жыл бұрын

Excellent update.

@thinkcartool3825 2 жыл бұрын

Muy buen canal de reparación de bricolaje, tenemos que contactarlo.

@ralphj4012 2 жыл бұрын

Another effect of applying three tons of sideways pressure to the probe tip, similar to what happens with DVM probes. Ho, ho. Everybody drops a clanger know and then, as long as you learn from them then that is fine. I once shorted a piece of live chassis equipment, and did a lot of damage, when using a grounded scope. Your misdemeanours are mild in comparison.

@mike-yp1uk 11 ай бұрын

That's always fun.

@garypoplin4599 15 күн бұрын

So, you were able to connect the ground probe of your ‘scope directly to the ground of your DC supply because both units are connected to mains through an isolation transformer? Is that right?

@FulvioGa 2 жыл бұрын

Great advice!

@Diebog 2 жыл бұрын

Hi do you have a video on how to us an oscilloscope?

@briang.7206 2 жыл бұрын

I often check my probe before using it. That way I know its working before taking a measurement.

@alimoradi2323 2 жыл бұрын

You're a legend

@PurityVendetta 2 жыл бұрын

I bought a Rigol DS1202EZ brand new, spoiling myself and replacing my old 70's analogue scope. Quite quickly I found that one of the probes was faulty and gave weird intermittent readings. Rigol replaced it no quibbles but I wonder if the standard probes can be a bit of a weak point as the scope is brilliant? May I ask a quick question? I'm relatively new to this level of electronics and wondered what is considered the highest voltage it is safe to put into my oscilloscope before I'd need to use differential probes. I've been very careful with grounds and voltages but it would be nice to know. Thanks.

@dalerobinsuk 2 жыл бұрын

It is common on Rigol probes for the ground lead to fail.

@LearnElectronicsRepair 2 жыл бұрын

The point of using differential probe is not so much to do with the maximum voltage as it is to do with where you can and can not connect the ground lead of your scope 😉

@reallyniceaudio 2 жыл бұрын

great tip! (no pun intended)

@KevinR242 Жыл бұрын

This did not show up when you compensated the probe, being that the probe was dropping the voltage same as a resistor.

@davinbrowne6429 Жыл бұрын

What’s the difference between Tmmbat42 and Tmmbat42film. Can I use film instead of tmmbat42

@HerrAlien 2 жыл бұрын

This means that we'll get a conclusion for the HDMI stuff :)

@tttttttt8482 2 жыл бұрын

Can you recommend a multimeter for a electronic beginner hobbyist. ?

@LearnElectronicsRepair 2 жыл бұрын

There are so many to choose from and a lot depends on budget as well. More will depend on who you ask! Probably any auto ranging multi meter with a fast responding 'bleeper' on the continuity range will be good enough for your use, of the three I use regularly I like all of them. The Aneng AN8008 is very nice to use and has good resolution (down to 1mV on the millivolts range, it has a microamps range I find very useful and reads resistance to 0.01 ohms. I would say it is the best all rounder of the meters I own and the highest resolution 1.999 digits. The Kaiweets DM601 has the nicest display and the fastest short/continuity indication of three. But my old Fluke 79 which I have had for years is the best in diode test mode as it gives one short bleep for semiconductor junctions and a continuous bleep for shorts - non of the other two do that and it is very useful for fault finding, but it has the lowest resolution of the three on ohms or millivolts (reads to 0.1 ohms). A second hand Fluke is a good choice, I've had mine since 1993 (new) and it's still working well. There is a newer version of the Aneng, called AN8009, which I haven't used but it looks to be very similar to An8008. Also there is the AN870 which looks very interesting and adds an extra digit of resolution again - so 1.9999V rather than 1.999V and is very well priced for this feature and comes well recommended by others. I haven't tried one yet myself though i will soon I'm waiting for a review sample AN870 from Banggood but the first one got lost in the post and the second one is stuck in customs somewhere at the moment

@tttttttt8482 2 жыл бұрын

@@LearnElectronicsRepair Thank you for your detailed response. I was thinking about AN8008, going to check for another ones you mentioned. Have a good day

@LearnElectronicsRepair 2 жыл бұрын

@@tttttttt8482 You will be more than happy with the AN8008 I Am sure

@trone32 2 жыл бұрын

No stupid mistake here Richard, think it must have happened to all of us at one point or another.

@LearnElectronicsRepair 2 жыл бұрын

True but you still feel pretty dumb when you do it again 🙄

@Plan-C 2 жыл бұрын

Had a similar thing with a multimeter. Turns out the battery was just low lol.

@des2610 2 жыл бұрын

I always test for DC voltages with my meter.. (Fluke of course!)

@LearnElectronicsRepair 2 жыл бұрын

The same advice extends to Multimeters (Fluke or otherwise), test leads and anything else you use in fault finding.

@des2610 2 жыл бұрын

@@LearnElectronicsRepair The road to perfection is paved by many mistakes!

@OldSkoolF 2 жыл бұрын

OMG... If I had a dollar for every bad ROC DMM probe I'd be a millionaire! I switched ALL of my probes and leads to Probe Master.. They're worth every penny in saved time and second guessing yourself... I've also gotten into the habit of testing my DMM after any high voltage work.. Bad fuses will also give you fits..

@Dmiliunas 2 жыл бұрын

Wow, ur a human. For a moment there I thought u are a robot or cyborg. Humans make mistakes. No big deal.

@neilw2O 2 жыл бұрын

Doh! Measure twice, cut once.

@khx73 2 жыл бұрын

I wonder if the 1x/10x switch has gone a bit dodgy? It wasn't exactly 1/10th the reading.. but close. Try it in 10x maybe?

@LearnElectronicsRepair 2 жыл бұрын

I would but it's in the bin now - I have 5 or 6 others 😁

@khx73 2 жыл бұрын

@@LearnElectronicsRepair Ah well, best place for it really! 😄

@paulc9139 2 жыл бұрын

School Boy error, NO treat's for you this week laddie.

@izzzzzz6 2 жыл бұрын

I thought you were going to sayit was a probe with a built in attenuator

@laptopDoctorKZN 2 жыл бұрын

We all make mistakes.. lol 😆 ..

@abeleski 2 жыл бұрын

So I told my wife that I need to first test it before I use it she was not amused

@ieronimosgr 2 жыл бұрын

same mistake and whit polymer probes... No work no good voltage no signal whay led its on i dont have voltage... Of course broken probes 80 minutes wasted times..... Stunit things (sorry for that) .... And olways forgot to test probes or broke in the job and dont anterstent... This another story....

@vicbushbashing8403 2 жыл бұрын

I need help I posted a comment on one off your videos could you please respond?

@LearnElectronicsRepair 2 жыл бұрын

Which video?

@vicbushbashing8403 2 жыл бұрын

@@LearnElectronicsRepair LER #036 - Circuits & Components for Beginners 5. Learn About Capacitors, Bad, Faulty, How They Fail

@wilsard 2 жыл бұрын

good grief. what are you gonna do? test all your leads and probes every day? it's gotta happen. we've all spent countless hours because of bad wires. so many times i've rewired some guitar pickups and stuff, and the guitar cable decided to go wonky in the middle of it. waste's so much time.

@LearnElectronicsRepair 2 жыл бұрын

It's a reminder that you should test your leads when you use them - in the same way I always test my probes by touching them together before taking continuity readings, I should touch your scope probe to the little calibration point you find on just about any scope. I usually just touch the end of the scope probe against my finger to see if I get 'mains hum' on the trace and if I do I assume it is good. This time it came along and bit me on the bum.