Edu09 calibration failed

Calibration results:

CH1 offset at 2V/div : 77 FAIL
Rounds : 51
CH1 offset at 1V/div : -46 OK
Rounds : 51
CH1 Y-position low, CH1_DAC1 255 0
Rounds : 33
CH1 Y-position mid, CH1_DAC0 255 77
Rounds : 51
CH1 Y-position high, CH1_DAC2 255 173
Rounds : 51

ic1 has 0 volts on pin 9 traced pin 9 to ic3 pin 22, from there i cannot locate were it goes. maybe im just going about this the wrong way.

Please check the voltage on pin 4 of IC2.
Should be about -5.2V.

For more info and possible resolution, please see these threads:
Calibration failure EDU09
Edu09 : Calibration failed (resolved)

yes i have -5.1 volts on pin 4 of ic2, with the software running on pin 1 of ic2 i have 1.01 volts

What is the voltage on pin 7 of IC2 when the software is running?
Should be about -1.7V.

yes i have -1.66 volts

What is the voltage on pin 2 of IC3 ?
There should be same voltage as on pin 1 of IC2.

pin 2 of ic3 has-0.27 volts pin 1 of ic2 has-1.88 volts

Next you can check the resistance between IC2 pin 1 and IC3 pin 2.
Disconnect the USB cable before measuring.
There should be 1.1k ohms.
If not, please check the soldering of R13, R3, IC2 pin1 and IC3 pin 2.


thank you! its working now i went back and rechecked all my soldering and now it calibrated!

No problem. Glad to hear it’s fixed. Enjoy!