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- Опубліковано 6 жов 2024
- Is a $7 LCR Meter / Component Tester from Ebay any good?
Dave tests the M328 (LCR-T4) model component tester.
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The original project name is AVR-Transistortester, opensourced firmware/schematic/documents maintained by German hacker Karl-Heinz Kübbeler.
I was about to say yeah it was the German dude who wrote the original ardinuo code. I love this little board is so handy for sorting through MOSFETs to see what they read it'll quickly identify any shorted or blown FETs
Dave, a guy with a $9000.00 rolex watch was once told by a guy that had a $3.00 digital watch "Nice wrist watch, it seems to be only a few seconds off"
WisdomVendor1 I stopped and gazed after reading this, true !
I'm more of an Omega man, so I'll go with that. Rolex is overpriced -- their prices have doubled in the past few years. Anyhow, with that said, I'll give you a bit of perspective on Swiss made watches. I know a $25 quartz Timex will tell time more precisely than a $5,000+ mechanical Omega Seamaster, but I appreciate the craftsmanship that went into it. Think of it like this -- if both watches cost exactly the same amount ($25), which one would you rather own and why? I'd rather have the mechanical masterpiece because I appreciate the craftsmanship, artistry, and engineering that went into it, rather than the quartz. Perhaps you favor the electronics of the humble quartz. Nobody passes down a Timex.
Espinosa versus Tano Cariddi? (water-wall-clock vs quartz-watch scene)
Wrist sundial gang where ya at?
@@explosivedude8295 nah.. prefer the wrist pendulum clock
Testing a piezo speaker is particularly fun, as you can hear it probing at the part to determine it basically operates as a capacitor.
Really interesting to get to hear it go through the motions though.
That is a great idea!
Dave, you can calibrate this device by shorting all 3 test points and pushing test. After a short process will ask you to remove short and at some stage ask to install a capacitor. Would be interesting how accurate it is after that process. Thanks for the vid!
Wait are you serious?? I've had one for a while and I never knew that! Where did you get this info?
it is written in the "manual" lol I used for weeks and was not getting the precise values that it was supposed to, so I checked the "manual" and there it was. Works perfectly. Have to calibrate every time and in each leads change btw
Does that mean that the calibrated values are not stored in eeprom? It should be relatively easy to fix that..
+Louis Stubbolo there are videos of people calibrating on youtube, saw them before I purchased one. Now you can get them for $10 with a case.
SirArghPirate They may well be stored in eeprom, but if you are using external test leads or a different set of pads to measure your parts then each set of leads/pads will have a slightly different innate resistance, capacitance, and inductance that needs to be accounted for. It is one of those things that must be calibrated out whenever you change leads and from time to time (such as with changes in environment) even on higher end LCR meters because it does not know when you changed the leads and that new calibration coefficients are now needed, so it is ordinarily a manual process. If using external leads you would ideally use shielded leads so that the leads do not interfere with one another nor pick up external fields that can alter readings (or else keep your leads extremely short). Typically you will have several sets of test leads ranging from alligator clips to SMD tweezers, etc., for testing various types of components, hence lead changes are not uncommon during use (and at other times you may switch to using the built in pads, which would also be equivalent to a lead change).
I am grateful Dave made this review as I am very impressed by the quality of the firmware and its overall capabilities. Even though I already have perfectly good transistor testers and very nice LCR meters I may still be inclined to order one or two of these in the future, preferably outfitted with a proper case for added protection just to compliment my other gear, or to loan out to others as I do not loan out my lab grade test gear.
One of these is all I have for LCR meter, and it's more than good enough. All I need one for is to identify messed up electrolytics that have caused a power supply to fail. Finding an electrolytic that should be at 1 ohm ESR measuring 35 ohms is good enough.
John Ridley same here
how accurately does it measure inductance?
I have that exact tester... It's true that the absolute measurements are a bit off, but it's fairly consistent when you repeat measurements, so it's great for matching components. I've used it to find the closest resistors in the pile, and to match MOSFET gain when rebuilding an amplifier. Fantastic bit of kit once you understand its capabilities and limitations.
I hope you've shortened the three inputs of your device and calibrated it. Because I have the same model and after calibration, it's pretty accurate. You can also upgrade the firmware on it using the original repository, but it's a little bit tricky.
How do you use to match mosfets Gain because I not seeing the numbers this is showing I'm trying to match irfp260n mosfets and Google is no help if I search what's on the display
Can this test components in a circuit without removing them?
@@irishguy200007 It will depend on the circuit, and the component being tested, as items can be in parallel etc. It's no different than with any testing.
Thanks for looking into this! Saw the furore in the mailbag comments and it's good to see you addressing it :)
Yeah, I didn't give it a fair suck of the sav.
EEVblog Yeah Dave, I've seen these being reviewed by other channels, I'm glad you gave it another shot since I was really waiting for your review on it before I add one to my setup. (Yours is the only channel I trust for reviews on test equipment)
Great! Now ship it to Big Clive so he can draw pictures and make it explode.
I think he has one, or I might just be thinking of Julian Ilett
Agent Smith - I know Julian has one for sure
- Eddy
Yep, thought that was pretty good at the time I saw it too
Pretty sure Julian has a ton of these. Just because. :)
msylvain59 uses one of these frequently in his teardowns.
Many of these units also offer a way to calibrate them and once done are pretty much bang on. Some of the software versions also offer more accuracy depending on the external ADC being used onboard. I have a couple of these units and they come in really handy for testing salvaged parts or doing basic transistor or mosfet matching.
If you press and hold the button a menu comes up with a number of functions including in-circuit ESR measurement for capacitors (without having to press the button each time), very useful.
Did u test the in-circuit ESR measurement ? What are the results is it really a 0.01 ohm resolution (or 0.1 Ohm depending on the version) ?
I've had mine for several months; *cute!* _...added a power switch to prevent any parasitic sucking juice out of the 9v battery._
Same!
That's nice, although these devices have such a small parastic draw, that it is practically unnecessairy.
I didn't have a spare 9V battery around so I used two 18650s in series, seems to work well so far :)
Depends on the version you got. There were some versions that would kill a 9V battery in a couple of months or less.
I have several versions. Even ones that are powered by a AA-sized lithium cell have the bad design of a resistive voltage divider before the power switch. That version mitigates the problem by a mechanical power switch and, of course, being able to recharge the battery.
I have owned one of these for about 3 years now. Two years back I picked up one of those DIY Kit mini oscilloscope and put it together on the booth table of our RV. To sort out the parts for the kit I used my version (A bit more developed then yours) to sort the parts for assembly. It did a great job. Since I rarely use surface mount, I have soldered alligator clips on the pads so I can hook to parts that do not fit nicely in the plug deal. I use it very often and it has always done a great job for me.
Lcr meters are super complex. The fact that this $7 jobby can get it done is astounding.
It's ballpark LCR figure only. Real LCR's use a higher frequency and test voltage than this little device is capable of. The K-Firmware from the OSHW project has a slightly more versatile measuring funtion that requires an ATmega328, a 16MHz Xtal, a relay, and a capacitor to add a Sampling ADC method.
is it too complex ?
iceberg789
Ok... detailed answer it is...
As a hobbyist I have been researching this project thoroughly for the last month, and I've been posting none monotized info on YT and the EEVBlog thread. (I couldn't care less if you check out what I've done so far,.. just saying it's there/I'm no EE/here's my citation of what I've researched so far)
I recall Markus R. -The Project Developer of the official M-firmware, said that the LCR limitation is due to the input/output limitations of the microcontroller. You need a more powerful signal at a higher frequency and most importantly a faster ADC. The internal ADC of the AVR MCU is the primary limitation factor in this device and the code has to wait on the ADC to catch up in several places. Even with an additional frequency ic and buffer circuit, the AVR MCU can't work fast enough for all channels. There are other OSHW projects that use an AVR MCU to create a more accurate LCR by dedicating everything to the task, at least so I've read and posted about within the last 10 pages on the EEVBlog thread.
This AVR TT project has already moved on to the ATmega644/1284/2560 because there is no more room in the 328's flash/eeprom with the popular auxillary options enabled. There are no clones available for the V2 project but there are DIY files for all versions of the project if you want a real AVR Transistor Tester instead of a cheap substandard design (says the guy that bought a clone...then started researching it).
This project actually started with an ATmega8, and grew to the 88, 168, and 328, because the firmware grew and grew over the years since 2009. It's already optimized between C and Assembly as well. The Devs are not inexperienced amateurs. The real project hardware development is actually based in the Russian thread. A lot of the communication between them and the devs is direct. The Russian's have a larger online presence of skilled engineers that like to post about their DIY projects much more than the English speaking community. Thus their 406 page thread versus the English 160 pages, (both are about the same size per page). The software is primarily on the German side with M-Firmware on the EEVBlog thread as well. This isn't some simple device that has room to improve, hundreds of people have already added their professional touches and suggestions to get the project to where it is today. This project is designed to have stupid-simple hardware (that ALL of the clones screw up) and extreme level software. The only way to really understand the entire project is if you speak fluent German, Russian, and English. Unfortunately, Google Translate sucks at Russian. This is why I created the image indexes for all of the forums (still working on Russian). Schematics are universal as are pictures of interesting hardware. By attempting to show you all of the images as quickly as you can visually register them I'm trying to help people search for what they want to research further using a translation program without attempting to read the whole thread like I am trying to do. I add almost all images with their page number referenced to these videos. Again, these are not monotized, and never will be. It's just something I am doing to share my notes as I explore the project.
thanks for all of that, i will now need some time to digest all that.
iceberg789
I don't mind explaining what you don't understand. I'm just a few years into learning this stuff myself.
These links are to posts where other people smarter than myself explain the LCR/ESR measurement capabilities of the device.
1. www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg530451/#msg530451
2. www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg195402/#msg195402
3. www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1050001/#msg1050001
4. www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg432772/#msg432772
Post w/links to other DIY dedicated LCR projects:
5. www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg526087/#msg526087
Some of the earlier info may be outdated as far as the specific limitations of the device. The functionality like test frequency are the things to focus on in these posts. Also the forum user named "Madires" is one of the two actual firmware developers. No one is more knowledgeable about the device than him.
Of course all of this assumes you understand things like ADC= Analogue to Digital Converter and how these devices operate (I like Bill Herd's explanation of ADC's on HackaDay ;)
Thanks for doing a follow-up and correcting the Mailbag vid.
Info like this on cheap stuff is invaluable to us small part-time hobbyists because we simply can't afford expensive stuff or can't warrant expensive for such low use.
I recycle hold electronic parts and i really like that meter. It makes it faster to identify the components so i can class them where they belong :)
Hey please do share some of your projects.
We've just outfitted all our labs at my university with a variant of these. We use them as pinout checkers and magic smoke detectors. Saves tons of time helping students. I've also grabbed a 74xx chip tester for logic gates; same reason, check for the magic smoke.(no kid your chip isn't bad, you wiring is)
Oh I didn't know there were 74 series testers like that. I certainly could use one, because my wiring often is bad!
Mythricia I've found two different models neither works for 100 percent of the series but they work well enough, and can be found from the usual overseas sources
You still use discrete 7400 logic chips? Heh, I TA'ed that class twice at 2 different universities, the second time it was all schematic capture and small fpga dev boards, and that was a number of years ago!
Well, as a hobbyist I rarely do things because they are practical or useful, using elementary logic is a lot more fun than just another microcontroller.
Nope
Nice to see that you made an additional video about that device, thumbs up.
Oh and what you want with that is to test, if the component you put in is OK or not and if the replacement part is somewhat close to the original part.
That's a very good idea. Sometimes you want components with some element of shittiness, like ESR, when you come to replace them during a repair. Or if a salvaged part is even worth keeping or if it falls below even lash-up standards.
Although considering the (shown) weaknesses of this device, you get a considerably good tester for an unbeatable price. We absolutely don't talk about high end precision in this class of pricing or manufacturing. In most cases the precision of the device is good enough to help you find out what you have plugged into the socket. Me and my friends ordered those from China. We like them.
I know I'm late to the party but I've got one of these and it's perfect, as you say, for checking pin outs on transistors etc. Certainly a lot quicker than trawling the net for data sheets. I also use it for checking that LEDs are working before soldering them to a pcb.
Good to see you following up on the last vid! At least our comments do not go unnoticed :)... also good to see you giving it a fair test :)
Sounds like they might do in the forum though lol
If I had the money for all the accurate test equipment, then I would be one of the 2 percent. This kind of tester is a great deal for the majority of hobbyists. But, these should have a data sheet that tells their measurement range for different types of components. If they can spend the time to tweak the firmware, they can document and provide that document to compete head to head with the others.
6:31
From product manual:
"The turn-on or turn-off voltage of the mosfet must be less than 5V, otherwise the measured result is only its equivalent parameters (diodes, capacitors, etc.)."
lol it costs R$150 (usd 40) on average here in Brazil. You can get a Fluke multimeter for the same price range here too. Strange economics.
A A ill definitely check that out. Even if they tax me 200% it’s still a bargain
I got one of these. I would not use it for a "final say" but it's a handy little bugger to just check stuff on the fly and answer the "what is that" situation. They don't work well on hall effect sensors when you don't have a magnet.
i've have the same exact one you showed there for about 6 months now....i salvage alot of parts.....this thing is the best tester in my shop when it comes to figuring out exactly what surface mount component i'm saving......
Sounds like it's time to buy a second one. :)
lol....i didn't see my mistype....
*fixed it*
@ EEVblog (Dave) are we at 20 years running since the first atmel code? I remember working on that project back in the day ... the original was just an atmel and the data sent over rs-232 with some shitty visual basic or delphi code I wrote back then ... ( It's been so long I really can't remember ) not portable NO LCD , NO 9v battery, no smd pads for the little tranny etc .. etc .. it was more of a bench-top concept at the time ... but, of course it had the zif socket ! I'm glad to see it has evolved to a really handy portable jobbie ! I have the updated binaries if you want to flash the atmel chippies ... to un-chinese it ! all you need to do is solder a few wires and run my patch and it will be much more accurate ! 🤔
Great now I'm buying another thing shown on this channel. That $25 multimeter works great. Thanks Dave.
SnarkyPosters - It's ok... i got the multimeter too. It _is_ pretty good tho...
- Eddy
I have a Victor VC921, which is auto-ranging, *_very_* portable, runs on two AAA batteries, shuts off automatically to save the batteries, and is nicely protected in a strong hard-shell. The leads are a bit short, but, other than that, I like it a lot, and it's available on eBay for around $11, shipped:
www.ebay.com/sch/i.html?_nkw=VICTOR+VC921
I picked one of these up a couple of years ago. She is a bit more refined then the one you reviewed, but not that much better..At any rate, two winters ago I got one of those little oscilloscope kits, complete with case and all. So, being in our Motor Home, some 1500 miles Southwest from my shop, I decided to assemble the kit on the booth of our RV, using a 5 volt portable soldering iron and that device identifier to sort and install the parts according to the chenglish almost instruction sheet, (Thank GOD it had photos of how it went together!) Well it never did work right, I guess, until last fall when I was typing my problem into a forum and read my own text, in which I discovered the problem. The rotary encoder was bad, I ordered in a new on, and now the little Oscope works just fine. A bit late because I had ordered a bit better kit, well larger not sure how much better, and have that one working like a champ as well, also using the little parts ID to sort the resistors instead of straining my old eyes trying to id those damn green-blue resistors that mask the true color of the bands. The second one came without a case so I ordered one separately. The outfit had to send me 3 damn cases before I got one that was not missing parts, or broken in shipment! I am a bit particular about such things even if it takes 30 days for the damn packages to get here from China.
this was quick, I knew a lot of people would comment on this one, other electronic youtubers regularly use these
I use mine all the time. It works fine for what it is. This isn't NASA.
yeah, well, Dave really didn't give it a proper chance in the previous video
Very glad to see him own it up and do a proper test of it
Yeah exactly, this is a componente identifier/tester, it is not a lab grade component characterizer. What people expect from a 7 dollar gadget...
thats normal thinking of modern people... it's like comaparing 200 dollar to some 20 dollar speakers and saying, that it it's automatically crap, just because it's not as good... it seems like people don't get price/performance
Amazing! Yesterday I bought one of this here, and I never thought they were 'known' in the world!! I'm pretty happy with it so far!
The AVR Transistor Tester project was started by Markus Frejek, Karl-Heinz Kübbeler, and the parallel firmware is done by Markus R. (Aka Madires) on the forum.
The project is OSHW and is designed for you to build yourself. The Chinese clones are just substandard copies. None of the clones meet the minimum required specs from the documentation.
Upcycle Electronics can you please link to that documentation so I can follow the instructions to build one for myself?
MadComputerHal
PDF Documentation from May 2017 (extracted from tarball and hosted for download):
www.avrtester.tode.cz/upload/ttester_en.pdf
Project Home Page:
www.mikrocontroller.net/articles/AVR_Transistortester
GNU Tarball Server:
www.mikrocontroller.net/svnbrowser/transistortester/
GIT Hub Copy of SVN Repo Server
github.com/svn2github/transistortester/
Found this about history (instructables):
Ideas behind this kit is started in 2009 by Markus Frejek as a thread on a forum.
Later (in 2012) Karl-Heinz Kübbeler started to work on the project.
this project continued to be more known, it was implemented in various forms over the time. Some enthusiasts have made it on breadboard, some have designed their own PCB's, single or dual layer; with thru-hole or SMD components... and so on.
Also, over the time, have appeared variants with graphic display.
The original diagram released by Markus in 2009 is what they still use 2023... There just some optimizations about 9V battery power supply and other displays. Original display was a HD44780 16x2 LCD.
Get a version with a socketed atmega. Read the original documentation: www.mikrocontroller.net/articles/AVR_Transistortester. Pop in a 16Mhz crystal, replace the voltage reference ($2 directly from TI) and flash the latest firmware. It will measure sub pF and nH easily and fairly accurately.
Since the socket wears out fairly fast, I bought some and insert one in the soldered socket. Easy to swap out when failing.
The thing is, 99.9% of the time 100 people out of 100 don't need to know the value of a component with any precision whatsoever, other then it being an actually functional part of the right kind, with a value on the order of magnitude you thought it was of.
Attila Asztalos Exactly, when was the last time a hobbyist or repair tech needed to know a value to any greater accuracy than 10% in reality? $7 device = good enough for Australia, or anywhere else for that matter.
A repair tech might actually need precision. But hobbyists? Just knowing more or less what the component value is will almost always be enough!
You don't need precision if all you build is LED clink circuits and alike. Shit tools makes same quality things.
This. Also when I measure capacitors all I'm really looking for is if the capacitor is ok or needs to be replaced, the ESR and capacitance readings on this do the job just fine (after calibration).
I must be the 0.1% - I'm looking to test [and measure! ] hand-wound coils and transformers.
I really love the Mtester I have for a couple reasons. 1. It can auto identify transistor polarity and pinout, which is very useful for unknown components. 2. It can do inductance to some degree, which for a cheap device like this is invaluable. As a beginner myself I would fully recommend any beginner get one of these, especially if they can afford better test gear like me.
The only quibble I have is that the socket is relatively fragile.
Prices rising in 3, 2, 1...
In Banggood this DMM is still at $17 in promo. Only eBay sellers rised prices.
Just ordered one for ~€5.50 so I guess it didn't happen that fast. Useful little device especially once you replace some of the clone parts for higher precision ones.
No clone meets the minimum system design of the project. AKA clones are junk...
That mainly happens with used equipment, not new.
prices drop ;)
I've used one very successfully to test dodgy electrolytics in various things and just checking if salvaged parts are reasonably good before putting them into the parts bin for possible use later. And it's just FUN!
I love it. So much I bought one. Not disappointed. It rocks!!! Cheers!
These things are a MUST HAVE for anyone doing entry level repair for stuff like car amplifiers or power supplies
Mine's a bit more expensive and its got a frequency generator/counter too.
Mine got a frequency tester and generator in as well. Just keep on pressing the button for about 5 sec and the menu will open.
I have had an earlier version of this device for a long time. I once assembled one of those little cheap oscilloscope kits using just that device to sort the parts, came out just fine considering I did the whole job on the booth table top in my RV sitting in the middle of the Mojave Desert using a USB soldering iron running off a home built power-bank made out of two 18650's taken out of a dead laptop battery. Both the tester and the little scope run fine. The only problem I have had with it is that I once put in to large a lead in pin hole 1, and it no longer makes good contact, so I simply used the lower set of clips on the zif socket... Thanks a million for the review though, I really believe all the hobby electronic guys should have one of these. I find it especially helpful now that I have begun to get surprise packages from Electronic Goldmine down in Arizona. for a few bucks they will send you a large box of mixed electronic parts from Diodes to Caps as well as all sorts of resistors and a ton of things I need the component tester to figure out what to do with. Some are beyond that device but I probably won't have any use for them anyhow, so in the bin with them.
Hahaha "I'm not going to quibble over that?" yeh right Dave.
"Go. No go" That's an engineering measure one does not hear often.
Even though this was 4 years ago, I better not hear about ANYONE giving Dave shit again. The man's an angel amidst the mobs of unworthy degenerates. Dave teaches us important lessons. Lessons on how to put away our savagery and strive for a bit of enlightenment. And I, for one, refuse to allow him to be chastised by the likes of us. Nuff said.
*I knew you would get "attacked" in the mailbag video for this!* LOL...
Have been using one of those for about the past 4 years, and it's been solid. Love it.
These ZIF sockets never actually say 'TEXTOOL'. If you look closely you notice that one of the letter 'O's has been changed, usually to a D or a Q.
LOL! Didn't notice that
Some people on the forums have said they had these fail. I don't know if the real ones create the same kind of stress for the pins that attach the ZIF socket, but the copy I have creates a lot of movement and stress on the pins/PCB/pads. Place the loose ZIF socket on a PCB, and try to hold it in place while pulling the lever. It really wants to move around with considerable force.
On all of the ones I've seen so far it always says TFXTDOL ... the one in this video included :D
John Howard
That's what I assumed as well. It looks to me like the pins have some leverage motion to them as well. It practically guarantees long term problems of lifting pads/traces, especially with inexperienced diy'ers and flux core solder alone.
My transistortester came with a 3M socket, no textool marking. I can't remember but it may have also had moving PCB pins
These are amazing devices for the price. As a Component identifier, tester, looking for "Gross" failures, it is a winner. Helped me fix a couple of failed TM500 series plug-ins, so more than paid for itself. Thanks for another honest review. This is why we come here.
The first idea was mentioned in Elektor Magazine in April 2005 and used a PIC processor AFAIK. It never took off, because of some dumb issues it had. Aparently all these chinese ones originated from a second design first posted on the german forum microcontroller.net. That is something like your EEVBlog forum, but much smaller since it's main language is german. www.mikrocontroller.net/articles/AVR_Transistortester
That’s pretty sweet. I could us3 this at work quite effectively
For 7.00 dollars, that's just brilliant, fricking brilliant
I have had one of these little toys in my kit for over 2 years now, and get a lot of use out of her. Since my income crashed last spring, and came out at 1/2 what I was making, the purchase of new parts has become a sort of thing of the past. Thankfully I have picked up several kits of cheap china crapware resistor packs, capacitor packs, and hundreds of LED's with a good selection of boards to build on so I can still have some fun. That said though, getting exotic parts has come to an end, and I have relegated to tearing down old power supplies and old PC Motherboards to supplement my parts bins. This little guy has become invaluable for such projects! I am considering soldering some leads on the external pads so I can expand the reach of the testing, as I rarely use it for smd parts and I do have some nice alligator clips that would work fairly well for that purpose. I did use it once for a large kit build a few years ago when I could still afford to buy a kit, and built up one of those cheap toy oscilloscopes using the tester to sort out all the parts since all the resistors were of the ugly blue/green type that strained my ancient eyes to try to determine the colors, this device paid for herself in just that one built! I have never built up a box for her, and I doubt I will ever get one now since groceries have a much higher precedence then electronics now days, and I do hate having the bill collectors at my doorstep, so much work scaring them away when I answer the door in my tight jocky shorts with a pistol belt around my waste and my old M1911A1 hanging from it in a military style holster. Seems they never return, and all I have to say is that they will have to wait their turn. (Just kidding, it isn't that bad yet, but my nightmares do offer great fodder for such ideas) Your breakdown on this deal is right on, I love my little device so much she occupies a nice cardboard box that a survival knife came in, the knife was crap but it had a nice box, almost worth the 5 bucks I gave for it at a roadside stand on RT 66 in Arizona a couple of years ago.
15:04 In AvE parlance, that would be a "sore dick deal" (ie. "can't be beat")...
I have had one of these for 12 months and I must say it does come in handy. Thanks for the revisit. Keep up the good work mate.
10:09
The body diode seems upside down.
But it got it right the previous time.
GpanosXP
Good catch. I have two Chinese variants on these (cases, colour displays) and they can do some odd things like this. If you consider these devices to be quick-check component verification then they're perfectly usable. Where you really want to nail things down then you're going to have to break out serious tools, or spend a lot of time and effort.
These would also be good projects for fiddling with, in themselves.
The orientation when you place it in the socket makes the difference. It bugs me to see, but it doesn't really matter as long as it identifies the drain and source pins correctly, which it does.
The Daniu tester I bought for $30 doesn't have any errors that I know of; it's a more polished product but at 4x the price. Seeing the limitations makes me appreciate the more expensive item more; I bought that one first but then got a couple of the less expensive ones based on the low cost, thinking they'd be essentially the same, but it's not.
I have three of these. One was assembled and two were kits. They work flawlessly!
"It calibrates easily with shorting the three leads, then you'd need a ~10nF and a ~20pF capacitors, and it's done"
Your tone of voice suggests that you are genuinely impressed with this product! I am very impressed and will likely buy one too. Thank you for sharing!
I'd be tempted to try things like two diodes together, 1 to 2 and 2 to 3, connecting parts of logic gates just to see what it does.
Two diodes work, e.g. a bi-color LED in 2- and 3-pin configuration
stonent it's actually really fun to see what they can and cannot identify. Linear voltage regulators, no dice, which isnt surprising really
Yeah I suspect they don't put out very much voltage in order to lower the risk of damaging something. So it may not be enough anyway to power up a 7805 fully. Maybe 7803 might trigger something.
The higher cost version can test a 30V Zener too, which the $7 one won't be capable of.
I had a failed power supply for a sat receiver, couldn't find anything obvious wrong with it, so i started pulling the electrolytic caps off it and used a similar tester, replaced all the ones it showed being out of spec and the power supply works like a charm now, don't remember what mine cost now, got as a kit from bang good, and 3d printed my own case. its been very useful and well worth the money and time.
How the heck did you miss the 8th all-time most popular thread on your own forum? Part of me thinks this is a ruse.
Nope, he's just a self unaware, pretentious snob
I have a similar one (but with a somewhat different firmware). For the price a surprisingly useful tool for identifying pinouts or function of recycled semiconductors.
Yes Those German's who Bombed our Chippy,s did an absolutely fantastic job with the firmware and software development for this device . Thumbs up and hats off to them. .It can also be re programmed with the latest software...Also they are very accurate when calibrated first...
Thanks for being positively surprise and not shredding it to pieces beforehand :-) I know you can be a bit focused on high-pricy and heavy equipment at times. But for everyone who just started with electronics, this seems like a nice allround starter thingy until one can afford a proper meter.
Nice save .
Troy Winterbourn nice smile
I did not know these existed, this is so frikin cool! I'm just recently learning that there is such a thing as open source hardware... fascinating and for some reason gives me a warm fuzzy feeling
Hey Dave! I'm doing a cool new mod kit for this already handy little device ! Here are a few of my ideas :
1) bin the 9v battery and the 7805 (I'll just hit em with hot air and wipe them off) then fit a nice lithium ion battery pack and a regulated charging board with a micro usb connection .
2) I've already 3d printed a really nice case for it which is much thinner so much more 'nerd shirt pocket friendly!' o_O
3) Modify the firmware! Why? Because I can! .lol Seriously though ... Although this is a great bit of kit AS-IS outta the box, I have found some discrepancies between my expensive proper equipment and this little gadget , of course! What do you expect for only $12 or less ???
They (we?) are already making this little Atmel stand on it's head and do tricks ! It takes quite a bit of m0jO to do all those a/d / d/a routines to work those FETs to get some great sampling nearly maxing out the capability of this little Atmel's resolution .. With that being said, I have gone over the code and patched it here and there to be a bit more accurate in some spots.. ;) Mainly, with the FET's and the gain! Resistors, caps , didoes, and general NPN or PNP transistors seem to be testing fairly accurate ... but as you know some FETs are sensitive lil buggers....
4) Other ideas that may or may not ever be implemented, but. I'm just tossing them out there to see what people might think would make it a bit better ! (Please post /share your own ideas on how it may be improved in the comments below) :
4a) Perhaps shitbin the whole board and lcd display design and just make a whole new much smaller PCB with just enough space to fit the atmel , the few support components , the zif socket and smd test pad .. and wire up a touch screen TFT display along with a micro SD slot so you may be able to store certain data on the components you test .. For example: you may want to test a bunch of FET's and perhaps pair them with others of similar gain .. or perhaps for quality control of some sort ie: run through a batch of parts and perhaps calculate a mean value of those that are within spec or tolerance and alert you if the next one you test is a bit off ...
4b) add wifi capability to the design so you may interface with your pc or other device to acquire and store that data in a database for whatever reason a tech or engineer may see fit for whatever reason ...........
4c) Perhaps expand the zif socket size to at least 18 pins and along with the wifi interface as mentioned above, implemented,.. Perhaps be able to flash microcontrollers with a bin over wifi from your pc or other device!
Just a few ideas I'mm tossing out there... let me know what you think .....
Cheers,
Kixxy o_O
And there goes the $7 price point
I built mine as a kit. I knew that it measured caps in circuit, but I could not believe that the seller told me that it tested other components. Actually, I also did not really know what it was. I like how it diagrams out MOSFETs and transistors.
Thanks
Frank
Frank Reiser Video/Audio Service
You can calibrate it short the 3 pin
Thats not enough. Exact procedure desribed in project manual mentioned there many times.
...but there's more....
In the official PDF the ATmega644/1284 Schematic shows the option to add a auto calibration feature using 2 spare pins, a 100nF capacitor and a 470k resistor. Others have suggested using a single pin to control a double pole relay that achieves the same thing by connecting the calibration circuit.
Hi Dave, thanks for video about this tester. I bought one about year ago. It was also marketed as capable of in circuit measurement. I used it to troubleshoot faulty caps in power supplies and various faulty circuits. Until last week. In one cheap powerbrick, there was capacitor and diode combination on the output. One of these pulses this tester sends to tested component posibly came back with higher amplitude, or maybe capacitor was charged. Anyway by my lazines not to remove capacitor for measuring, ATMEGA8 is fried, while there is no isolation between component and procesor. So maybe this device is too simple. But anyway it bringed me lot of help with good/bad component troubleshooting.
As you Said, there are hundred Models Out there, Not everyone is good. Not everyone is Software upgradeable. So which Version ist Worth buying if one needs a good esr Meter and what is hackable/ upgradeable???!
Axel Werner also interested.
If you need a good ESR meter than I would just go for an official ESR tester. These things are good but its really easy to accidentally kill them with a charged capacitor and sometimes long test leads can make the ESR test vary wildly.
today ebay showed one for $2.42 .. but i didnt notice if that was Aussie$ or USD's ... If it's Aussie, then the USD price would be .. lemme thing: ya, they have to put $1 in the package for you ... !!
I have got the same thing it on my work desk for 2 years and It's very useful, especially when you have many things to solder on PCB . Chinese manufacturers made it for 10 usd, including plastic case .
Can't believe Dave is impressed by a Chinese diy kit :)))
I'm impressed by what the firmware is capable of
It does have German Software in it ;-)
oh shut up
I have this one and one with a colour LCD that does a lot more tests. They both manage to test on a really weak battery, the colour one actually tests right down to 5.4V and reports Battery Empty at 5.2V. I do get one weird reading, with a damaged White led that should be 2.9V it will read 3.6V and a leakage of a few nA with 12pF. Occasionally it reports 0000000F so the leakage does odd things to the capacitance test. That led causes a long pause on the green tester and a blank line where the capacitance should be. I tested electros that I pulled out of an old computer power supply, bad esr on everyone of them. That supply had ten years of use so not surprising. The colour one has an acrylic case and measures a lot more plus it has voltage terminals and an audio frequency counter and signal generator. The generator has a bunch of spot frequencies from audio to over 1Ghz. You can choose your own foreground and background colours plus testing can be automatic or select the specific test from the menu. I actually damaged a led by inserting two LEDs and it detected them as a diac and tested for reverse breakdown. Oops!
Can this thing test ICs, like a 555 timer or other small ICs like a a 4011 nand gate or 4049 hex inverter for example?
btw Dave, thanks for another bang on video. Yahoo seriously mate, turn up the ride and throw another shrimp on the barbie, b/c this vlog makes me smile more than a vegemite sandwich, just bang on mate. (I would have added "that's not a knife ... now THIS is a knife," but no one under 40 would get the reference)
No.
The original programm is from Markus Frejek
Link: www.mikrocontroller.net/articles/AVR-Transistortester NOT www.mikrocontroller.net/articles/AVR_Transistortester
if you connect leads 1, 2, and 3 together and press the test button, does yours run a calibration dialog?
Mine does, tried to measure an apparently fried thyristor that was fully conducting in any direction and it hopped into calib Mode.
Good on you Dave, learning as you go and not afraid to admit it!
IF you're heavily into discrete component salvage business, I can see how this thing would appeal to you.
Was thinking of basically that but like also just for sorting a old mismatch of parts or something. Simple and easy as well so could give it to an inexperienced person to do for a while.
My main use is after breadboarding and experimenting I have a "discard" pile to sort through. Sometimes I let it build up a little and it becomes unmanageable. This makes it much faster for me.
Thank you for doing a great job running your tests on this unit. This answered many questions I had about it. Awesome!!
What happens if you test a component tester with another component tester?
that how they make babies.
They will cancel each other out.
It starts a new Big Bang
I really need one of these in my life. Awesome bit of kit.
Probably not. It's never good unless it's one of those highend professional things for 1000$. This is EEVblog after all xD
This dude is such a pretentious snob, and he's apparently completely self unaware and happy about it. How repulsive.
Domino52o
Have you been at the glue again?
@@daverhodes382
Can you not see it and hear it in him? Well, birds of a feather i guess.
I got one of these ages ago but mine was faulty. It turned out to be a bonus because I had to fix it! When I got it working it became pretty useful to identify parts quickly
Been around for years. Dave's late to the party ;)
Digger D hey...I know you
I'm putting the acrylic case on mine as I watch this video. Thanks EEV, great buy for the budget
Always discharge capacitors before measure them in those devices. I killed one of those testers a while ago with a still charged electrolytic cap... No magic smoke though :(
Also: since caps are measured by charging them and counting the time for that, the measurement is more accurate (if this thing is ...accurate :)) with a fully discharged cap.
obelix Good point, I've killed two testing electrolytics now.
I accidentally connected a partially charged 25v 4700uF to mine and it actually made the unit power up on its own as soon as I connected it. Luckily it survived but I always short them out first now even caps that are not charged.
Sounds like a good feature to add... a couple of relays that short the pins until the testing starts. Connect your part... it's safely discharging until you press the button. It can go back to discharging as soon as the test is over. Now you know it's discharged when you are done!
There is a design variation with a shorting relay that is supported by the existing software. The relay coil current is far more than the rest of the circuit draws, so you don't see it on commercial boards.
Why do I remember this? A capacitor charged to 19V blew up my first tester...
Right! All the test inputs are directly connected to microcontroller I/O pins.
So, connecting a capacitor charged to more than 1 volt may damage the µC by causing currents through the internal I/O protection diodes. More than 6.5 volts will definitely kill it.
The tester tries to discharge a connected capacitor by shorting all three test pins (by setting them all to output with a logic low) for a few 10 ms. But that may not be enough to completely discharge a large electrolytic cap.
for years I also been over looking this kinds of units and I finally cracked and bought one! it actually came in very hand when I was assembling a board that was designed in the usa and the kit came with European components which meant the BCE was all backwards ! it paid for its self right there! by saving me the trouble of finding all the datasheets for each transistors
Lately EEVBlog videos feel like: "I'm just gonna say a bunch of stuff and then correct it with annotations"
LOL, you're new here right?
My *slogan* from day one has been "off-the-cuff".
I press record and talk, that's how I've always done it.
Agree, off-the-cuff lets us know we're listening to an honest person, not spit-polished BS snake-oil salesmen.
That's pretty much how we communicate these days isn't it? Mike just will correct himself and make it obvious.
Besides... "IT'S FREE!!"*
*Just pay a separate fee, S&H fee, document fee, credit card processing fee, cash sales fee, VAT, tariffs, taxes, duties, customs fees, import fees, export fees, and FOB fees for on site pick-up. Model shown is not item for give away. Model discussed is not item for give away. Model demonstrated is not even manufactured by the manufacturer of the item for give away. Item for give away does not actually exist as there is no such thing as a "free lunch".
30% restocking fee on all returned free items. $10 dollars per day storage fees for free items not collected after 10 days of notification. Not for issuing notifications to winner. It is the responsibility of winner to inquire if they are a winner or if there is a contest/free item. NO REFUNDS.
I love my component tester as a simple double check before soldering ass saver. On more than one occasion, I've been unsure of the pinout of a given part. It saves me from digging up a datasheet for it on the computer, but more importantly, lets me confirm at the workbench, letting me install and solder in a part with the confidence I'm not going to do some idiotic move like put a transistor in backwards. Nice to characterize SMD caps too, since those are typically unlabeled.
Anyone got a link to a good one on Aliexpress?
What these things are great for is hobbyist repairs. If you have the schematic, or even not, and you've got some suspect caps or transistors, you can test if they are in the ballpark of if they are goneski. With one of these, a cheap thermal cam, a sig gen (just a PC sound card) , a cheapo DMM and a rudimentary scope, you can fix just about any audio amplifier
I have one
The "grandaddy" of all these testers was the Peak Atlas DCA55 Digital Component Analysers. I was working in the R+D lab of an electronics factory when it was first launched. One day, in about 2000, a sales rep turned up to show off a DCA55 and an ESR meter for testing capacitors. I don't think anybody who saw that demo on that day _didn't_ want a DCA55, right then and there ..... We ended up ordering one of each instrument for the lab. Most of us who were present ended up ordering our own DCA55. The ESR meter didn't have anything like such a "wow factor" about it, but it proved its worth anyway as it made the repair of switched-mode power supplies feasible for once.
This device tests more components than the "original", and comes at such a fraction of the cost, it would be churlish to protest at the absence of _in situ_ ESR measurement (you will save more than enough to afford a separate ESR meter anyway). Absolute accuracy is less of a big deal; most of the time you will be wanting a simple "yea or nay" indication whether a component is good enough, and sometimes you will need to find 2 transistors with the same gain.
Anyway, it's always worth having two versions of a test instrument: An expensive one that gives accurate results, and a cheap one for everyday use that won't matter so much if you blow it up. Big thumbs-up for these little beauties!
Dave, I really like your channel and your in-depth reviews of electronics technology. However for this video you apparently did not do any research. What you essentially trash, complaining about non-critical features such display brightness and missing low voltage indicator, has been carefully designed by two trained engineers such as yourself (Markus Frejek and Karl-Heinz Kübeler), documented on the well known German microcontroller.net website and is shamelessly more or less well copied by companies in China that sell their knock offs online. You received a particularly old and poorly executed clone. The project is continuously evolving, with improvements to both hard- and software. The latest version is quite capable. So please RTFM (131 pages), buy or build the most recent version (EagleCad schematics are available too) and do a new video. We all know you can do much better!
www.avrtester.tode.cz/upload/ttester_en.pdf
www.mikrocontroller.net/articles/AVR_Transistortester#Introduction_.28English.29
github.com/svn2github/transistortester
www.ebay.de/itm/142477623934
+Wetter Station I did NOT purchase this, it was sent into my mailbag.
EEVblog Hi Dave, sorry I did not know you received it for free. I corrected my post. Nonetheless, perhaps you can at least add the 131 page manual from May 2017 link and Github software link to your video? I'm sure your viewers would appreciate that.
Ain't nobody got time for that.
Dave's viewers, keeping him honest! ;')
+Wetter Station, thank you for posting this information.
Thanks to seeing this video just today I ordered one of the latest versions with a color oled display in a case with test leads and some misc parts to test it with. 21.84 shipped from New Jersey to my place in Portland Oregon. I remember trying to find a capacitor tester back in the day and I have a couple transistor testers but not a all in one unit with a nice display. Of course back then there weren't any, at least none I could afford.
I might not use it a lot now but I still fix my own stuff when it breaks and this will be so handy.
It can even show remote IR wave forms and has a rechargeable battery built in.
Man buys something cheap and complains. Why does it have a backlight! If it didn't have one you'd complain about that.
Actually, I think he said pretty directly that it did impress him.
A most interesting idea. Just got an LCR meter but this would certainly help as eyesight starts to get tested on smaller coponents
I have a varient of this with a color screen in a case with proper buttons. I like it. I don't consider it THE definitive answer, but it gives some pretty good general guidelines.