Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: joesatch on September 25, 2024, 11:56:24 am

Title: diode cathode
Post by: joesatch on September 25, 2024, 11:56:24 am

pot into diode added to cold clipper. What's this do?  I tested it and it gives interesting gain characteristics not simply like a parallel resistor

Title: Re: diode cathode
Post by: pdf64 on September 25, 2024, 07:02:15 pm

The normal cathode V DC there is typically 2 to 3V, so the diode should be forward biased, conducting.
From a DC perspective, the cathode voltage will drop slightly.
From an AC perspective, the impedance at the cathode will pretty much halve, so stage gain will increase, probably nearly double, so maybe 5 to 6dB.