Chuck,
I've noticed too the same weird behavior of the pots on the front panel. It's like the FW value isn't synchronized to the real pot position unless the whole CW-CCW-desired position swing could be made.
Also I'm very reluctant to replace any ICs on the A5 board since it's difficult to find NOS circuits of exactly the same type which are not fake. I just wanted to find the way how to test the multichannel DAC and multichannel ADC at the system level (in terms of performance).
One more thing:
By mistake while in CAL02 I've set the output generator voltage from 0 to 5V square wave instead of requested 0 to 10V and the calibration routine passed this step!
Now I wonder whether the requested "standard calibration signal" must be bipolar?
Maybe 500mV from -250mV to 250mV? 1V from -0.5V to 0.5V and so on?
Could you, please, check on your side the calibration signal amplitude and levels?
I remember that before having TG501 I've tried to pass the CAL01 with the fast pulse generator w/o any success. However, once I've got TG501, the things started to move. Maybe also as you suggested the standard calibration signal is not correct?
Thank you,
All the Best,
Maxim
