[sdiy] Oberheim OB-XA autotune procedure questions

[doof]

Hi all,

I've just finished replacing the battery in my OB-XA (along with installing new bushings and cleaning some problematic J-wires) and I've found that all voices now fail the autotune procedure.  When I press the button, it cycles through all 8 voices, then the 8 LEDs flash for about 2 seconds.  All 8 voice cards are perfectly functional.

I have both versions of the service manual, and neither address the autotune function other than using it in calibration routines.  How autotuning is implemented and any specific troubleshooting/calibration strategies are completely neglected.

So I'm wondering what could possibly be contributing to this problem.  Autotune worked before the battery replacement, although tuning wasn't perfect.  Does something within the circuit rely on battery power to retain memory for the autotune algorithm?  

At first I thought bad tuning might be causing the problem.  Turning the voice disable feature off with the test2 switch, I've started calibrating the individual voice boards to achieve better tuning, yet reagardless of the more accurate initial tuning the autotune function still does not want to cooperate.

Looking back at the AH archives, it seems a few people have experienced this exact problem, though no answer ever surfaced.  

...Anyone?

Thanks.
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