$20 LCR ESR Transistor checker project

[hapless]

Hmm... Let me try.

tom666 USBasp
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg810893/#msg810893

tom666 Arduino
https://www.eevblog.com/forum/testgear/lcr-t4-mtester-v2-07-lcr-meter-black-block-issue/msg879842/#msg879842

Mauro's message with the ICSP connector on the banggood tester
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/msg854124/#msg854124

Mauro's tester in the case
https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/?action=dlattach;attach=202981

[mauroh]

Thanks    I corrected my previous post 
Mauro

[Radio Tech]

Interesting information. I may be able to do this.

I like the way you added the header to the device for programming also. Could do it on the bread board but have to locate the missing 8MHz crystals I ordered 

[ogara]

I bought a LCR T4 Mtester last year, graphic display, yellow PCB but only started on it now.  It starts up with only Mtester logo msg, no other version or model numbers visible. 

Did a upgrade apparently without issue, need only to change to "CFLAGS += -DLCD_ST7565_V_FLIP=1".  This is from the "transistortester-master\Software\trunk\mega328_st7565_kit\Makefile", which I understand is the "K" firmware.

I also try to upgrade to the "M" trendy firmware specifically 'ComponentTester-trendy-1.22m' but only ended up with a blank display.  Did tried playing with the obvious settings in the config.h but no luck getting the right combo.  I find its settings layout more daunting but is my tester even compatible with m-firmware?

[madires]

Yes, ST7565 is supported by the m-firmware:

Code: [Select]

/*
 *  Chinese clone T3/T4 with ST7565 display
 *  - thanks to tom666 @ EEVblog forum
 */

//#if 0
#define LCD_ST7565R_SPI
#define LCD_GRAPHIC                     /* monochrome graphic display */
#define LCD_PORT         PORTD          /* port data register */
#define LCD_DDR          DDRD           /* port data direction register */
#define LCD_RESET        PD4            /* port pin used for /RES */
#define LCD_A0           PD3            /* port pin used for A0 */
#define LCD_SCL          PD2            /* port pin used for SCL */
#define LCD_SI           PD1            /* port pin used for SI (LCD's data input) */
#define LCD_CS           PD5            /* port pin used for /CS1 (optional) */
#define LCD_DOTS_X       128            /* number of horizontal dots */
#define LCD_DOTS_Y       64             /* number of vertical dots */
#define LCD_START_Y      0              /* start line (0-63) */
#define LCD_CONTRAST     11             /* default contrast (0-63) */
#define FONT_8X8_V                      /* 8x8 font, vertically aligned */
#define SYMBOLS_24X24_V                 /* 24x24 symbols, vertically aligned */
//#endif

If you need to flip the y direction:

Code: [Select]

#define LCD_FLIP_Y                      /* enable vertical flip */

And if you got a small x offset enable or disable:

Code: [Select]

#define LCD_OFFSET_X                    /* enable x offset of 4 dots */


[ogara]

Thanks, I tried again, enabling/disabling all 3 ST7565 section with LCD_FLIP_Y but still no display .  Any other switches I can try?  I have also tried changing the contrast numbers around.

[madires]

Is the LED lit when the tester is powered on? Rotary encoder?

[ogara]

It doesn't have a led but the LCD backlight does come on for some seconds and no addons yet, still factory default. 

[madires]

And you've also updated the EEPROM?

[ogara]

Yes both ComponentTester.hex & ComponentTester.eep, using a batch file to flash to avoid mistakes.

[vinceroger]

Hi i new too this site just came across it whilst searching for some build instructions for this tester i have just brought can anyone help with a link etc many thanks in advance

http://www.ebay.co.uk/itm/331873741389?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

just had a thought are the resistor values etc marked on the pcb already? i usually buy this type of tester pre built but thought i would have a go at building a kit form one.

[bitseeker]

Welcome to the forums, vinceroger.

The PCB has all the parts identified on it. So, build instructions generally aren't needed. Here are some tips:

1. Put the lowest components on first (e.g., resistors) and work your way up (IC sockets, capacitors, transistors, connectors).
2. Before installing the microcontroller and screen, power up the tester and verify the voltages on the IC socket and LCD connector. This is your only opportunity to make sure that you won't fry anything.
3. Once everything is working, be sure to calibrate it. Your kit may include an extra capacitor for this purpose.

The listing below has a photo of the assembled PCB without the screen that might be useful for reference:

http://www.ebay.com/itm/272165236396

[timofonic]

@c4757p
@madires

What about the madires' feedback? Is an interesting project and he might provide some interesting feedback.

Even better: If submitted to GitHub, many people would fork or and provide interesting modifications.

It's a popular product /project too, a cool "Made with KiCad" logo in the schematics and PCB would be interesting too!

[madires]

Yes both ComponentTester.hex & ComponentTester.eep, using a batch file to flash to avoid mistakes.

Still no output at all? That's strange! Maybe some 5V<->3.3V issue with the display? The mega328_st7565_kit's Makefile has LCD_SPI_OPEN_COL disabled. So it must be something else. Unfortunately I don't got that T4 clone. If the manufacturers would send me their clones it would make things much easier.

[vinceroger]

Welcome to the forums, vinceroger.

The PCB has all the parts identified on it. So, build instructions generally aren't needed. Here are some tips:

1. Put the lowest components on first (e.g., resistors) and work your way up (IC sockets, capacitors, transistors, connectors).
2. Before installing the microcontroller and screen, power up the tester and verify the voltages on the IC socket and LCD connector. This is your only opportunity to make sure that you won't fry anything.
3. Once everything is working, be sure to calibrate it. Your kit may include an extra capacitor for this purpose.

The listing below has a photo of the assembled PCB without the screen that might be useful for reference:

http://www.ebay.com/itm/272165236396

Well the kit has just arrived the bad news is the pcb has none of  the parts identified on it bacically its mark r1 r2 c1 c2 etc no instructions either in the package and the seller hasnt got any either i will try to upload a picture later but without knowing what value resitor/capacitor etc goes where im a bit stuck.

[madires]

The transistor tester's circuit is fairly simple and the clones are all based on the basic circuit in Karl-Heinz' doumentation. Please see https://github.com/svn2github/transistortester/blob/master/Doku/trunk/pdftex/english/ttester.pdf for the circuit. Why don't the sellers just put a note with the project's URL into the bag? 

[bitseeker]

Unfortunately, most of the sellers that carry the various testers based on the original design know little to nothing about them. So, I doubt they'd even know where to get a link to the project and its documentation.

@vinceroger: Sorry to hear that the silkscreen on the model you received was so sparse. As madires said, you'll be able to refer to the original schematics to identify which component fits where. There isn't a huge variety of components, which makes the task less daunting than it might at first appear to be.

Take a photo of the bare board (both sides) before you begin. If you get stuck, you can post your questions and the pic here. After you've finished building and testing it, if you're so inclined, it'd be great if you could post an updated version of the photo with the component values inserted.

[ogara]

Still no output at all? That's strange! Maybe some 5V<->3.3V issue with the display? The mega328_st7565_kit's Makefile has LCD_SPI_OPEN_COL disabled. So it must be something else. Unfortunately I don't got that T4 clone. If the manufacturers would send me their clones it would make things much easier.

It works now, my bad, I must have set and left the contrast higher while editing the config.h file.  The (M12864 DIY Transistor Tester) section with LCD_FLIP_Y disabled works best.

[vinceroger]

Unfortunately, most of the sellers that carry the various testers based on the original design know little to nothing about them. So, I doubt they'd even know where to get a link to the project and its documentation.

@vinceroger: Sorry to hear that the silkscreen on the model you received was so sparse. As madires said, you'll be able to refer to the original schematics to identify which component fits where. There isn't a huge variety of components, which makes the task less daunting than it might at first appear to be.

Take a photo of the bare board (both sides) before you begin. If you get stuck, you can post your questions and the pic here. After you've finished building and testing it, if you're so inclined, it'd be great if you could post an updated version of the photo with the component values inserted.

Im just measuring all the resistor values in the kit and also seeing what the four transistor part numbers are the rest i have already figured out.

[bitseeker]

That's great. You're quick. By the way, what speed crystal did they use on that model? 8 or 16 MHz?

[vinceroger]

That's great. You're quick. By the way, what speed crystal did they use on that model? 8 or 16 MHz?

its a 8 mhz crystal
transistors are 2x c945 p331 1x 4673 4c gf 2 1x ws tl431 928
resistors x6 10k   x2 1k   x2 27k    x3 470k    x1 470 ohm   1x 33k  x3 680 ohm   x1 100k  x1 560 ohm  x2 3.3k   x1 2.2k there is also x1 brown looking type resistor but it only has 1 black band dead centre of it ('0' Ohm jumper) ive now been advised but there are 23 resistors in this kit plus the odd brown one but only 21 resistors fitted too the pcb when assembled thanks guys for any help you can offer me in building this kit.
                       

[stj]

EZM328A files for johnka

[bitseeker]

there are 23 resistors in this kit plus the odd brown one but only 21 resistors fitted too the pcb when assembled                       

I'm not quite sure I follow. You listed 23 resistors and I see 23 spots on the PCB for them (R1 - R24 minus R11, which isn't there).

[onlooker]

The PCB showed 2 R1s. One of the 2 should be R11. It may be misprinted or damaged.

[bitseeker]

Good eye! I see it now. The R1 next to R10 is probably R11.

So, there are spots for all 23 resistors and the zero-ohm jumper.