gints oleg (GO) esr meter

[peter g]

hi forum members, I have just finished the construction of the GO esr meter. i'am trying to calibrate it. the problem is, the zero adjust drifts after its set. has anyone built this meter? i'am not sure if i'am adjusting it right. help needed. thanks.

 

[Kripton2035]

some translation from the russian documentation...

Setting. 
 First Time - check for +5 V and after 78L05 
-5V (4.7V) Output DA4. 
 By choosing R31 achieve normal contrast on the display.
A little about the buttons: 
 Enabling device while holding down the Set button turns it into install mode 
 correction factors. There are only three 
 - Channel 1 Ohm, 10 Ohm and capacity. Change 
 factors + and - buttons, record in the EEPROM and bust - 
 same button Set.
There is also a debug mode - this mode to 
 indicator displays the measured values ​​without treatment - 
 to capacity - the state of the timer (about 15 samples per 1 uF) 
 and both channels measure ESR (1 step ADC = 5V/1024). 
 transition in debug mode - Pressing the "+"
And one more thing - zero adjustment. 
 This is closable entrance, press and hold button "+" 
 and through R4 are making the minimum reading (but not zero!) 
 simultaneously on both channels. Without releasing the "+" button, click 
 Set - the indicator will display a message on the Conservation of U0 in the EEPROM.
Next, measure the resistance of 1 ohm model (or less), 10 ohms 
 and capacity (you trust), we determine the correction factors. 
 can turn, turn while holding down the Set button and set the 
 to-you, respectively, the results of the measurements.

more here :
**broken link removed**

 

[peter g]

thanks a bunch krypton, i'll try it and post back.

 

[peter g]

hi krypton, finally got around to adjusting the go esr meter. been pretty busy cleaning up after Irma. when I short the test leads and hold down the plus switch, the display shows the one ohm and 10 ohm correction factors screen? so cannot zero adjust. the whole calibration procedure seems confusing.

 

[peter g]

trouble found (solder short) all is good.

 

[peter g]

I spoke to soon. still having problems. I did the adjustments and the meter adjusted the way its supposed too. the problem now is it won't measure esr of a capacitor larger than 500mfd. display shows all zeros?please help!

- - - Updated - - -

I spoke to soon. still having problems. I did the adjustments and the meter adjusted the way its supposed too. the problem now is it won't measure esr of a capacitor larger than 500mfd. display shows all zeros?please help! I built the version using 16f877a chip.

- - - Updated - - -

spoke too soon. adjusted the meter per instructions. the problem now is I can't read the esr of a cap that's greater than about 500mfd. any ideas?