[sdiy] Buchla 100 oscillator - bad ua726?

[mark verbos]

Hi guys,

I have a Buchla 100 series oscillator with stability problems. It works 
fine, except that sometimes it drifts away from pitch as much as a few 
steps and then later settles again to the same pitch it was originally. 
I have tried it on several power supplies, so I know it's not the power, 
and I added a 220uF cap to the power lines coming in and it didn't help. 
Is this the sign of a bad uA726? How would I test it? Any ideas?

Mark