Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: astronomicum on June 17, 2022, 09:53:42 am

Title: Univox U1221 Plate to Plate Resistor Mod
Post by: astronomicum on June 17, 2022, 09:53:42 am

Working on a U1221 with a 330K resistor placed between the plates of the PI Preamp and the PI. Anybody have any idea what the purpose of this could be? Thanks.

Title: Re: Univox U1221 Plate to Plate Resistor Mod
Post by: sluckey on June 17, 2022, 11:31:38 am

I'm guessing it's a NFB loop. It's not on the schematic.