I am trying to decide between tertiary winding for cathode fedback to be run with a pentode connected final, or U-L in the traditional fashion. I also don't quite know where the u-L point exists for the 813, that is at what percentage should the tap go. A tertiary winding that is ~30% of the anode winding takes up a lot of room. I don't think of any over ~15%, like Acro's 350 and Dynaco's A441. I have a pair of 441's and they need to be better. they are acceptable, but that's about *IT*. I need a stellar one...

I think I will go with a cathode tertiary winding. It will net me ~80W without getting to nutsy with dissipation and I can put g2 right where I want to. Fortunately I have a reasonable design OPTx for both apps. I just need to decide.

On the schematic distribution. I am going to draw them tomorrow and the next day. Such things need a good proofing I can say with confiddence. Also notes on limitations, and variations. more importantly Limits are a personal requirement. Then off to the scanner and ~4 pages at ~1 meg each ought to be fine resolution.
regards,
Douglas