Hey-Hey!!!,
I found a few causes of noise. part was a routing. I ran the choke leads too close to the voltage refrence boards. I moved this and a lot of it went away. the other was harder to figure. I changed the orientation/location of some of the bits on the voltage ref. boards. They were picking up interferance and pluging it in where the circuit was quite sensitive.I think the last can be adressed with a seperate filament TX. I have two 6.3 and a 5VAC winding in series feeding a bridge and I *SUSPECT* that if it were on a different core I would be free of its infulence.
Also, the active load/output buffer works best with a 12GN7 and a 12BY7 instead of two of each. Now to re-wire and plug in the 7788's I have in place of the 12GN7's. 50 mA/V gm ought to help...instead of 36 mA/V. If I can avoid creating an RF oscillator.
regards,
Douglas