$20 LCR ESR Transistor checker project

[Jacon]

Mouser is backordered on the MCP1702-5002E/TO part.  Any suitable alternates?

https://www.tme.eu/en/details/mcp1702-5002et/ldo-unregulated-voltage-regulators/microchip-technology/mcp1702-5002eto/

196 pcs as of now   

[RGK]

Mouser is backordered on the MCP1702-5002E/TO part.  Any suitable alternates?

https://www.tme.eu/en/details/mcp1702-5002et/ldo-unregulated-voltage-regulators/microchip-technology/mcp1702-5002eto/

196 pcs as of now   

Hoping to stick with Mouser and definitely USA.  Digikey has the part, but also need some parts that they don't carry, so trying to avoid multiple vendors.  Mouser does have the similar MCP1700 (max 6V) and an STMicroelectronics part.  Safest bet is to get the single MCP1702 from Digikey @ $0.51.

BK

[bitseeker]

You can also check Arrow. Sometimes they have stuff cheaper than Mouser and DigiKey, or free shipping. Their site can be cumbersome to find parts, but it can be worthwhile.

[madires]

A quick update on the ST7735 offset issue. The new m-firmware version will have an X and Y offset setting for the ST7735.

[RGK]

Do I understand correctly that if I build an "AY-AT" kit with all the supplied cheapo parts and substitute the high-grade parts jakeisprobably listed in post #3893, minus the 20MHz crystal, that the unit should power on run properly without updating the firmware?

BK

Assembled with all the high-grade parts and seems to be working well!  Still need to equip myself with the necessary tools before updating to m-firmware with crystal swap.  Thx for the good info.  Now to measure hfe of 400 parts...

BK

[technogeeky]

Apparently Vellman is selling a "K8115" component tester kit. For $65.

 

I guess it's about what you expect from full retail markup, but still.

[bitseeker]

Gee, not even a case.

[madires]

No LED, 78L05, LM385Z2.5, probe/test resistors possibly 1% tolerance, and a CD4050 as level shifter for the display. A very basic tester for 65 bucks.

[imidis]

I understand a mark up but that's more like robbery. 

[bitseeker]

Yep, but not everyone puts forth the effort to avoid being robbed.

[madires]

And some good news We proudly present 1.32m:
- Additional output of components found to TTL serial interface.
- Driver for TTL serial interface (hardware and bit-bang).
- Updated var_russian.h (thanks to indman@EEVblog).
- Added support for X&Y offsets to ST7735 driver.
- Changed configuration of battery monitoring. Added switches to disable battery monitoring and to support an unmonitored external power supply.
- Added configuration switch to reverse operation mode selection at startup (UI_AUTOHOLD).
- Improved filter for Germanium BJTs with high leakage current in detection function for depletion mode FETs.
- Added fancy pinout to PCD8544 driver. Also fixed error in the PCD8544 driver's function LCD_CharPos() for rotated output.
- Improved functions for fancy pinout of 3-pin semiconductors and moved some functions to display.c. Output of pinout on separate screen if required.
- Added indicator for usage of external voltage reference (Show Values).
- Improved IR decoder and added optional protocols.
- Added more protocols to IR RC transmitter.

And thanks to indman for the vintage Germanium BJTs.

[mebel]

Does anyone have the same problem with AY-AT? On Karl-Heinz Kübbeler software everything is ok but on Madires software there is a problem with capacitance measurement. The results are always about 4% less than it should be( I have checked that with a multimeter). Sometimes after programming the microcontroller (and callibration) it will happen that the result is very close - but it happens only once and never again.

[indman]

mebel,Markus firmware and madires firmware is the same!
You, probably meant Karl-Heinz Kübbeler  firmware?

Madires, big respect for your hard work!
I will a little add the list of changes in comparison with version 1.31 -
you added the beautiful vertical 8x16vfp font (gratitude to his author of NIckNI@VRTP.RU and Gennady_13@VRTP.RU for adaptation to the project).
Here is how version 1.32 with a new font on WEI_M8 clone looks

[mebel]

mebel,Markus firmware and madires firmware is the same!
You, probably meant Karl-Heinz Kübbeler  firmware?

Yes, thanks.  I corrected.

[madires]

Does anyone have the same problem with AY-AT? On Karl-Heinz Kübbeler software everything is ok but on Madires software there is a problem with capacitance measurement. The results are always about 4% less than it should be( I have checked that with a multimeter). Sometimes after programming the microcontroller (and callibration) it will happen that the result is very close - but it happens only once and never again.

Have you measured a film cap about 220nF to 2.2µF a few times before running the self adjustment? It's explained in the README.

[mebel]

Yes, I did that. I printed and read whole instruction.

[madires]

Do all caps read low or just a specific capacitance range?

[mebel]

It seemed that the smaller ones ( for example film cap 100 nano) were quite ok

This evening I will check that more precisely. I will check the same capacitors with Kubbeler firmware, your firmware and then with multimeter.

[mebel]

Do all caps read low or just a specific capacitance range?

Here are the test results on the latest firmwares.

Capacitor          Aneng AN8009        Kubbeler             Markus
1µF                         950nF               982nF(.13)            979nF(.78)
2,2nF                     2,241nF             2,230nF               2275nF
10nF                       9933pF             9914pF                10,04nF(100.3)
100nF                    103,4nF             103,7nF(.63)        105,2nF(7.28)
1µF                         988nF                973nF(.10)          1008nF(.77)
100µF                     95,4µF               93µF(.27)            86,27µF(.30)
10µF                      11,56µF              11,64µF(.83)       11,07µF(.84)
1000µF                  998µF                  976µF(.09)          923µF(.09)
470µF                     477nF                 471nF(.13)          454nF(.05)
2200µF                  2218µF                2120µF(.04)        1998µF(.06)
2200µF                  2126µF                2106µF(.09)         2005µF(.08)
100µF (400V)         100,4µF               99µF(.34)             95,78(0.33)
2200µF (old one)   2104µF                not checked          1945(.09)

82µF (100V)             78µF                  not checked           71µF (.06)

             


                 

[madires]

I don't know why your tester reads larger caps a few percent low, but you could change the correction factor. Look for following lines in function LargeCap() in cap.c:

Code: [Select]

    if (Mode & PULL_10MS) Value /= 109;   /* -9% for large cap */
    else Value /= 104;                    /* -4% for mid-sized cap */

Large cap means capacitance > 47µF, and mid-sized cap 4.7 - 47µF. Simply lower the divisor to get a higher capacitance value.

[dave356]

Hi Guys,

I have a question on replacing the TL431 vref with the LM4040 in the mega328 kit.  I'm trying to remember from somewhere in this thread
if the 4040 is pin compatible with the 431.  Somethings telling me that it wasn't pin for pin.

I'm getting ready to assemble one of the kits, (have 2) but can't remember about the 4040.

Help will be appreciated,

Thanks

[mebel]

Hi Guys,

I have a question on replacing the TL431 vref with the LM4040 in the mega328 kit.  I'm trying to remember from somewhere in this thread
if the 4040 is pin compatible with the 431.  Somethings telling me that it wasn't pin for pin.

I'm getting ready to assemble one of the kits, (have 2) but can't remember about the 4040.

Help will be appreciated,

Thanks

[RGK]

Hmmm, in that case I installed the LM4040 into my AT-AY incorrectly.  Post #4052 shows it correctly done?  Likely undamaged??

BK

[mauroh]

And some good news We proudly present 1.32m:
- Additional output of components found to TTL serial interface.
- Driver for TTL serial interface (hardware and bit-bang).
- Updated var_russian.h (thanks to indman@EEVblog).
- Added support for X&Y offsets to ST7735 driver.
- Changed configuration of battery monitoring. Added switches to disable battery monitoring and to support an unmonitored external power supply.
- Added configuration switch to reverse operation mode selection at startup (UI_AUTOHOLD).
- Improved filter for Germanium BJTs with high leakage current in detection function for depletion mode FETs.
- Added fancy pinout to PCD8544 driver. Also fixed error in the PCD8544 driver's function LCD_CharPos() for rotated output.
- Improved functions for fancy pinout of 3-pin semiconductors and moved some functions to display.c. Output of pinout on separate screen if required.
- Added indicator for usage of external voltage reference (Show Values).
- Improved IR decoder and added optional protocols.
- Added more protocols to IR RC transmitter.

And thanks to indman for the vintage Germanium BJTs.

Hi Markus, thank you so much for the new firmware!!!!
I quickly tested it mainly for the TTL Serial output implementation and even though I have several thinghs I would like to point out (I got use to the K-firmware serial output... ) I'm quite happy with it.
I enabled it via bitbanging on the M12864 banggood kit, and since I already wired it on PC3 as output I changed the pin assignements to use it and it works fine.

My main consern is that not everithing that I see on the LCD is sent to the serial port and when I enter the main menu nothing is sent to the serial output.
Only once I was able to see the menu on the serial but I can't replicate it.
BTW, at the end of each line of the menu a CR should be sent otherwise the menu appear as a long sentence.
On the k-firmware I discussed with karl-heinz a secondary option that send (only on the serial output) at the beginning of each line the number of display line that the text will be sent. This semplify alot the the interpretation of the strings by a companion software.

Great Job!!!
Mauro

[Miwer]

Hmmm, in that case I installed the LM4040 into my AT-AY incorrectly.  Post #4052 shows it correctly done?  Likely undamaged??

BK

I can confirm post #4052. I installed it like that in my AY-AT, and it's working fine.