Full Circuit Schematic Draft 2017 AVR Transistor Tester Component ESR LCR Meter Frequency Generator
Vložit
- čas přidán 6. 07. 2017
- You've found the Ultimate DIY Tutorial Guide to the - M12864 Transistor Tester. FULL CIRCUIT SCHEMATIC created, Parts Detailed, PCB Fully Retraced, from the 2017 version of the Atmel AVR, German designed, Chinese cloned component tester. This is the latest version of the graphic LCD display component tester. Learn the difference between versions, how to build, modify, and use this device.
There are 2 testers that look very similar, with a similar footprint. The easiest way to differentiate between them is to look at where the PCB is labeled, "Transistor Tester." The newest version is red in color, the older version is white. The newer version also has the "T" in the word "Tester" capitalized, the older version does not have the "t" in "tester" capitalized on the PCB.
The key features of this design are the addition of Frequency output and measuring functions, and the TFT graphic display, with a higher resolution. There is also a voltmeter input that is intended to be used with an additional zener threshold voltage circuit.
The most important features when considering different clone versions are:
1.) The use of an external precision voltage reference IC.
2.) The implementation of TVS circuit protection.
3.) Designed with an ATMEGA328P in a replaceable DIP socket
4.) A crystal oscillator instead of the microcontroller's internal RC oscillator.
Design features this version doesn't have:
1.) ISP programming header/connections
2.) Official project firmware.
3.) Capacitive trimmer for the crystal oscillator.
4.) ResistiveTrimming.
5.) Buffered protection for frequency measurement and voltmeter terminals.
6.) A respectable endurable enclosure with post '90's aesthetics.
7.) A full Circuit Schematic with a complete list of component designations.
Follow me as I break down every detail of this project step by step in the coming weeks. Let's figure out how to turn this convenient little clone circuit into a fully functional tool with all the bells and whistles, while making sure we figure out how to use every feature we already have.
Project Goals:
-Fully document every detail of this circuit.
-Record every step of the build.
-Power the device from AC mains.
-Create an Upcycled useful enclosure.
-Explore all options for upgrading and adding on to the hardware of the circuit.
Project Links:
Official English Project Documentation
Version 1.13k (2017 May 26)
PDF Direct Download Link
3.39mb
131 Page Document
www.avrtester.tode.cz/upload/t...
Official Project Overview/Repository Links/Firmware in German, English, and Russian:
www.mikrocontroller.net/artic...
The original TT project founder Markus Frejek's forum post that started everything in 2009 (German)
www.mikrocontroller.net/topic/...
The chief developer of the project, Karl-Heinz Kübbeler, made it accessible to people around the World when he took the lead in 2012. Thanks to both of you.
Schematic Notes:
I wanted to try drawing a schematic by hand for fun. I have not had any formal EE training. I have maintained the original component designations with 2 exceptions (sorry). The capacitors designated "C3" and "C10" on the original schematic are not used in this version of the Chinese Clone. I reused these designators in other locations. Technically "C3" is still between Vcc and Ground, but it's location on the schematic is more appropriately located near it's PCB location. I change C10 entirely to account for the capacitor located near the TVS Suppression IC that did not have a designator.
I caught several errors I made during the process of tracing out this circuit. The largest ones are corrected as best as I can tell. A few minor ones I know about but didn't address in time are the trace between the PNP S9012's emitter and the HT7550's input. I connected them early on but somehow that connection was lost.
The original schematic has 2 resistors designated "R14." I relabeled the one used for the LCD backlight as "R14b." Unfortunately, I missed it on the final version of the schematic, where I added the picture of the PCB with all designators. It has the second to last PCB image before I relabeled the second "R14."
Music by: Martin Gioani
www.martingioani.com/
Creative Commons Attribution License
By order of appearance:
All of Me (Jazz Manouche) +Free Tab + Backing Track
• All of Me (jazz manouc...
I'll See You in My Dreams (Jazz Manouche)
• I'll See You In My Dre...
Jazz Manouche Guitare Improvisation : dans quelques semaines !
• Jazz manouche sur Guit... - Věda a technologie
I've already caught 2 errors in my schematic. I missed the 27k resistor before pin 12 on the Atmega328, and I also missed the Vcc rail designator above the capacitors at pin 7 of the ATmega328. I will clarify and demonstrate every connection in Part 2 ;)
Lovely content! Keep it up!
Nice project
Excellent video 👍
great vid, great job. Got here after burned mine with a capacitor. I was there for a while and when I turned tester on there was even a pop. Seems to be dead, no led, no screen.. checked all resistors and they looks fine. All board has Vcc but never turn on.. any hint? :)
Probably fried everything. The links in the description have all the stuff you need for building your own or uploading new software to a new 328 MCU. The eevblog forum thread has tons of people that have had the same issue, not read the forum post and asked the same question and had it answered again.
Honestly, of all the clones of this project, just order a $5-$6 T3 tester from China. If your going to go through the hassle of programming, get the official pdf documentation and build your own version 2 of the project using an ATmega644 or ATmega1284.
I have all the major clones and am working on two of my own PCBs of version 2 of the official project, an SMD version and one with a THD-MCU. Of all the clones the T3 is by far the best value because of the SMD test pad design. None of the clones have accurately built the project to the specifications in the documentation, so none are particularly good. The only drawback to the T3 version is the exposed LCD flat-flex cable. Most likely, this will be the failure point you will experience. I have bought two due to this. Don't bother with the cases for this model either. They make the SMD test pad unusable. The T3 has the best sorted simple software functionality too. The people making these clones tried to do some half baked modifications to remove things like the credit to the original designers of the project after they downloaded the software from the project SVN. The AY-AT and Little t clones have poorly running software that tends to glitch and have some problems. The T3s are pretty much disposable for the price to boot ;)
-Jake
@@UpcycleElectronics Super Jake! Thanks for your time and explanations. I really don't want to go that deep! :) I'm a beginner and was having some fun trying to fix it but better save it for spare parts and order another one! Learned a bit about the tester but still a lot information anyway :)
Great Video and I have one kit just like yours acquired on the usual places online. Mine does not work. And I've checked every component the thing just lights up the screen when I touch the encoder button and then ... nothing else happens. The DC jack connects directly to a S9012 pnp transistor. The output of the collector on that transistor is the input of the 7550 linear regulator. But on my module the problem is the output of the transistor is ... 0 V! Vemitter-ground is about say 9.41V and Vbase-ground is about 9,38V 0,02 ...i don't think the pnp is correctly biased and hence the linear regulator does not provide voltage to the circuit ...
Also I've found something really really Strange to say the least ... pick up a dmm on continuity test mode and the Pin 7 on the atmega328 is actually Connected to ground! It was supposed to be VCC!
I made another test. I connected a 12V spms to the input. It worked like a charm ! Booted, shows the menu the all thing ..except ... it started to smell funny ... that so known pre-(Magic smoke) typical smell :) ... I unplugged the 12V smps psu and ..indeed the Both the 7550 and the S9013 were hot. they did not reached the point of generating magic smoke since it was only for a brief seconds the device was open. I suspect the S9012 may be not working correctly.
I can measure after unplugging the power that both the bias junction voltage is about correct. both on Base -emitter as well as base-collector.
Other then that I think I will order a few more kits. Or even wait until the new version being developed becomes more mature and then i will build my own.
where did you get your Transistor tester?
I will not purchase from that seller again. Liers suck and any seller that uses a loophole in the postage system to alter their apparent shipped-from location is totally worthless in my opinion. If they need to lie to make a sale how will they handle their potential mistakes and problems?
keep my eyes watching !! waiting for whole project done :)
I has a problem with my transistor tester, it power off after i press the encoder, It only stays on when I keep the encoder pressed
karl heisenberg
Have you gone through the PDF guide from Karl-Heinz?
www.avrtester.tode.cz/upload/ttester_en.pdf
Pages 21 and 37?
Upcycle Electronics Hello, I downloaded the pdf, and read the schematic on the official site, luckily I found the problem, when I press the rotary encoder, it enters the menu, but when I release it it turns off, if I keep pressing it it enters the first one Option is selected, in this case, in the transistor option, and a message (Vext = 0mV) flashes.
I performed the following test, I made a jump between pins 1 and 5 of the rotary encoder, and with this jump, the meter performs the measurements normally, but when I release the jump, from pins 1 or 5 it turns off. There is another question when pins 1 and 5 are jumped, I can access the menu by rotating the rotary encoder, and when I press the encoder button, it accesses the selected option, by releasing one of the jumpers 1 or 5 the meter does not turn off, while The encoder button is pressed, but when you release both buttons, when you release the jumper between pins 1 and 5 of the encoder it switches off.
I do not know what's causing this problem.
karl heisenberg
Someone had a similar problem on the English Forum here
www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1126301/#msg1126301
...and his solution here:
www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg1142828/#msg1142828
There are several troubleshooting posts by the experts in between those two. I think your experiencing a similar problem.
Upcycle Electronics After breaking his head for hours, carefully examine the schematic, I decided to invert the power led, and the transistor tester it worked without problems. As absurd as it may seem, the LED was drawn inverted on the pcb, and I had soldered the anode and the katode, according to what was on the pcb. What madness !!! (I.e.
problem solved!!!! finally
karl heisenberg
I'm Glad you got it fixed.
Do you have the AY-AT (the same PCB Kit as the one I showed here)? If you do what are the numbers on the board? This PCB should have 2578AY-AT and another "K" number. The most common number is K103603BS.
I have notes on 6 different versions. I am working on a video describing everything we know about the different copies from China. I have collected most of my data on the AY-AT already. The issues with this board include none programmed ATmega microcontrollers, backward facing TVS IC's (SRV5-04), backwards facing, TVS diodes, and one person that had a bridged trace under the solder mask. All of the issues seem fairly typical for any mass produced product where the manufacturer is not employing rigorous quality control measures.
A couple of further notes on this model:
1.) Be very careful about discharging capacitors thoroughly before testing.
2.) The SRV5-04 is a 4 terminal TVS array, but it only has 3 of the 4 pins connected, Pin 1 is open. If you plan to use the frequency measurement or Voltmeter terminals you can gain a bit of extra protection from connecting either terminal to pin 1. (TVS protection is effective protection from small slaps like electrostatic, but it can't take a punch like a charged capacitor)
3.) The 'voltmeter' terminal on the AY-AT is actually intended for the Zener Threshold circuit from the project PDF. Just add a DC converter circuit in a boost configuration, set up for 40volts at around 1mA.
4.) The 3× 470k and 3× 68ohm probe resistors typically shipped with the AY-AT kit are wrong, the kit is shipped with 1% resistors instead of 0.1% (yes it makes a difference). If the last color band is brown they are 1%, violet is 0.1%.
5.) The kit is shipped with a HT7550 regulator and TL431A voltage reference. This regulator/reference are totally wrong. No reference is needed if the regulator itself is a precision device. The cheapest option is to replace the regulator with a MCP1702 5v LDO Regulator and omit the voltage reference in the firmware, (requires updating firmware). Alternatively a cheap LM4040 AIZ2.5 (0.1% accuracy) voltage reference can be added. The TL431A is only a 1% accuracy device (the Texas Instruments datasheet indicates 3 versions of this device A=1%//B=0.5%//"Standard Grade"(unmarked)=2% 2:08. The HT7550 regulator is a 6% accuracy device (+/-3%). The only way a voltage reference is helpful in the software is if it is around 10× more accurate than the regulator itself (at least that is how Markus (the co-developer of the firmware) described it, if I understood him correctly. The software compares the MCU's Vcc voltage to the voltage reference to 'figure out/decide' what 5 volts really is. Nothing is accomplished by giving the device 2 inaccurate references.
6.) There are a few firmware options and minor hardware upgrade options available for this unit/circuit. The Zener Threshold tester, Infrared Decoder, and Optocoupler Tester are all easy to add.
7.) Lastly, the m-firmware version supports the rated maximum clocking rate for the ATmega328 of 20MHz, both M and K firmwares support 16MHz clock speeds as well. This is an easy upgrade to do. Just replace the crystal and reconfigure the software in the Makefile. This upgrade greatly increases the screen refresh rates for the Color TFT display. This display requires a lot of data (8bits per pixel instead of 8 bits per line for graphic monochrome displays). This causes the screen refresh times to be terrible. The SPI interface is bit banged due to the available port structure of the ATmega328. The Chinese copies use a smaller font size to try to get around this. The whole screen can be utilized, and even some color options, if you upgrade the firmware and increase the clock speed. The 16MHz crystal doubles the speed. This also increases the accuracy and dynamic range of several measurements within the software.
I am no expert. I am simply doing my best to consolidate and repeat what I have read.
....and now I have my 1st draft for a AY-AT write-up.
Wishing you all the best, -Jake.
Hello. I have this device.
However, the device broke down due to incorrect measurement.
I need software now. I'll buy a new processor and install its software on it.
Can you send the software to me
Although this was not one of your Goals, is it possible to get the source code for the Firmware? Thanks. Great Video, BTW.
I will try to sort it out as best I can soon. From my understanding the firmware version is shown when you go through the calibration routine. This lets you know what official version it is running.
I have been researching the project extensively over the last week. One of the firmware developers Markus R. is on the main EEVBlog 150 page forum thread discussing and supporting users. He does one of the 2 firmware forks of this project. The other fork is done by Karl Heinz, also the author of the pdf documentation I showed parts of. There are apparently a few variations between them. Both versions are open source, are annotated in English, and available from GitHub and the Mikrocontroller SVN server.
On the clone, I believe there are some code variations that have to be commented out and a few pins changed for this clone's configuration. I plan to show all of that as I go, but I need to get on a real computer to do that. So far all of my videos have been done completely from my phone.
After posting my 'sloppy schematic' on the EEVBlog thread I got a bit of push back, so I've used the last few days to try to build a better filming setup where I can get to my computer at the same time I film. Hopefully I can finish filming part 2 in the next few days. I'm partially disabled. On my best days I only have 1-3 hours I can do anything physical that requires sitting/standing. Sorry if it seems I take ages to complete these projects. Thanks for the comment.
tkarlmann
The actual links are as follows:
*Official German Forum w/English info*
www.mikrocontroller.net/articles/AVR_Transistortester#Introduction_.28English.29
*SVN Server*
www.mikrocontroller.net/svnbrowser/transistortester/
*EEVBlog Forum Thread Mentioned*
www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/
Who is playing that wicked guitar ?
I know, right?
Best of all Martin tabs the whole thing out for guitar, provides the backing tracks, and gives lessons on his channel. It's mostly in French, but outstanding stuff. He does multiple styles on his channel but I've been partial to his reimagined 1930's "Gypsy Jazz" acoustic style. I've been begging him to do more of this compositional style. He's done about 10-12 tracks over a few years. He's definitely worth checking out.
Music by: Martin Gioani
www.martingioani.com/
By order of appearance:
All of Me (Jazz Manouche) +Free Tab + Backing Track
czcams.com/video/0s-h5Aa9zlg/video.html
I'll See You in My Dreams (Jazz Manouche)
czcams.com/video/acB9DbTTfbU/video.html
Jazz Manouche Guitare Improvisation : dans quelques semaines !
czcams.com/video/UtHBtyNBOkw/video.html
Thanks for the info ! I am an aged Django Rinehardt fan who often with Stefan Grapelli on violin brought that that Gypsy style to an admiring jazz audience. I will check on those contacts. Many thanks !