$20 LCR ESR Transistor checker project

[TheSteve]

I was sent these three files, they are instructions, schematic and parts location. - I have not yet verified the schematic matches the board.

[bitseeker]

i found the top image, but no underside shot.

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg964111/#msg964111 

[stj]

i found the top image, but no underside shot.

https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg964111/#msg964111 

wrong kit - that's the GM328R from EZM studio, i'm looking for the TFT kit with the red pcb.

[bitseeker]

I see. Unfortunately, that was the only one I saw both sides of.

[stryker]

Actually there are some Chinese $20 LCR testers that come with adapter for SMT parts for a long while but not as well done and integrated as the russian units.

They do look well constructed - have you bought a russian kit, or from that seller? 

[indman]

stj,Look according to this link, here I have all information on this clone and the photo.
https://yadi.sk/d/SPMZccK-smKEf   

[imidis]

wrong kit - that's the GM328R from EZM studio, i'm looking for the TFT kit with the red pcb.

So, I don't know about the EZM studio, this is mine (see attached)

[stj]

that's what i was after - thanks.
i wanted to see where the smd protection diodes were fitted.

i also see a big space along the top edge - perfect for a 10pin programming header - perfect.
well almost - they should have included it in the design along with a 16MHz crystal. 

[bitseeker]

Yeah, I was a bit surprised that after including the protection diodes, etc., that they didn't use a 16 MHz crystal. Odd.

[imidis]

that's what i was after - thanks.
i wanted to see where the smd protection diodes were fitted.

i also see a big space along the top edge - perfect for a 10pin programming header - perfect.
well almost - they should have included it in the design along with a 16MHz crystal. 

Glad to help  , it also had me fixing on solder point and cropping off a a piece that was bothering me LOL, the things you notice in photos.

That would have been nice indeed. Got it from a seller alicehappy on ebay, it took 38 days to get here from HK for around 13 US.

[all_repair]

Actually there are some Chinese $20 LCR testers that come with adapter for SMT parts for a long while but not as well done and integrated as the russian units.

They do look well constructed - have you bought a russian kit, or from that seller?

I got 3 Chinese LCR meters now.  So the next one need to have a big improvement to justify for my space.  I did bought a ESR meter from the Russia seller before.  Form factor is good, but has no input protection and my 2nd carelessness of putting a 12-50V charged cap killed it totally.

[Willem52]

Got my M328-KIT-CTFT working after getting a replacement M328p IC.
Indeed, they used the older 1.12k firmware.

I would like to see the newer versions with color settings too

Here some pictures I took when I got the kit.

[madires]

I would like to see the newer versions with color settings too

That's something for the ATmega664 or 1284. I'll put in on the to-do list just below touch screens With the ATmega 664 we have enough pins (and flash memory) for driving touch screen controllers.

[indman]

I would like to see the newer versions with color settings too

Hi, friends! Karl-Heinz Kubeller made new revision of a firmware of SVN 681 for a clone of M328KitTFT which allows to set up font color and back color through the menu.

[hapless]

Got my M328-KIT-CTFT working after getting a replacement M328p IC.
Indeed, they used the older 1.12k firmware.

I would like to see the newer versions with color settings too

Here some pictures I took when I got the kit.

Wow, a lot going on on the inputs. Makes me wonder how high the stray inductance and capacitance are on this one. Also, what's the power consumption? Something tells me that a regular 9V battery won't survive very long in it even if the crystal remains at 8MHz, let alone 16.

[imidis]

About 23.27 mA

Edit, modified with average

[hapless]

Backlit color LCD + MCU with <25mA average during testing? OK, color me impressed.

[jasonmrc]

I was sent these three files, they are instructions, schematic and parts location. - I have not yet verified the schematic matches the board.

I bought the same kit and i was sent the same files. looking at the schematic , the battery is wired funny/ wrong . both terminals looks like they are being shorted ..

i am looking in designing a case for this little test equipment .. and print it later !

[jasonmrc]

I would like to see the newer versions with color settings too

Hi, friends! Karl-Heinz Kubeller made new revision of a firmware of SVN 681 for a clone of M328KitTFT which allows to set up font color and back color through the menu.

look here if you want the english version
https://github.com/svn2github/transistortester

[stj]

given the present space situation,
i wonder how much bytes extra are needed for the colour display.

also, i'm sure most of you have seen the one sold by TomTop with a multi-colour display - be nice to get the code from that!

[madires]

given the present space situation,
i wonder how much bytes extra are needed for the colour display.

Not much (directly), but driving the display becomes slow because the firmware has to send a lot more of data. For a monochrome display it's a byte for 8 dots. For a color display it's a color value (12-18 bits) for each dot. And since color displays usually got more dots anyway, it becomes even more worse. That also requires a larger font which increases the firmware size indirectly.

[stj]

well that's an issue, i am already at the point of limiting the font size to keep the serial port.

[Willem52]

What would just upgrading to a 16MHz clock do...
It could help a lot in this situation, not?

[madires]

Not a lot, it's just a factor of two If you like to get an impression about the issue please watch a full screen clear for an ILI9341 based LCD. Anyway, a 16MHz crystal will also help with several measurements (inductance, capacitance, frequency) and the squarewave gen. And both firmwares support 16MHz for a long time now. Actually I'm surprised that most clones still got 8MHz crystals.

[stj]

i would like to see someone work out the delays needed to run the atmel at it's rated 20MHz myself