"Cathode feedback is used in this diagram. The secondary of the OPT's are connected to ground on the PC board so a separate connection is not needed. Note the reverse connection of the output transformer secondaries. 
This is needed on many OPT's to get NEGATIVE feedback to the cathode of the output tube. If unsure of your particular OPT's try wiring the secondaries each way (swap the two secondary wires, leave the primary alone). Chose the connection that produces the lowest volume."
I think Gery at Transcendar is going to build me some custom 20w opt's with 40% ul tap. Question is-does anyone know if the transcendars need reverse connection of the opt's secondaries for UL. I know I can try it both ways, but it would be nice to get it right out of the gate.
This is needed on many OPT's to get NEGATIVE feedback to the cathode of the output tube. If unsure of your particular OPT's try wiring the secondaries each way (swap the two secondary wires, leave the primary alone). Chose the connection that produces the lowest volume."I think Gery at Transcendar is going to build me some custom 20w opt's with 40% ul tap. Question is-does anyone know if the transcendars need reverse connection of the opt's secondaries for UL. I know I can try it both ways, but it would be nice to get it right out of the gate.