Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Jack1962 on April 05, 2015, 07:38:09 am

Title: Ampeg VT-40 Screen Grid Question
Post by: Jack1962 on April 05, 2015, 07:38:09 am

On the schematic it shows C302b(filter cap for the screens) to be connected to C207(a filter cap for the Bias circuit) . Would it not be a better to connect the  negative lead of C302b to ground?

Title: Re: Ampeg VT-40 Screen Grid Question
Post by: sluckey on April 05, 2015, 09:36:25 am

Quote from: Jack1962 on April 05, 2015, 07:38:09 am

On the schematic it shows C302b(filter cap for the screens) to be connected to C207(a filter cap for the Bias circuit) . Would it not be a better to connect the  negative lead of C302b to ground?

It's just drawn funny, but it is connected to ground (actually thru the STBY switch and a diode). Stare at it for a while and you'll see that it connects directly to the negative side of the bridge and the CT of the HT winding for the screen supply.