I am looking at using the 829B in a single-ended application with both halves in parallel. What can I expect for dissipation per plate? The data sheet is misleading, as it is assuming intermittent operation in an RF amplifier. What would be a good plate and screen voltage?
Take a look here...
http://www.pmillett.com/829b_amplifier.htm
From Pete
I'm running the 829B's at about 80mA, B+ of 320V, with cathode bias. For details look at the schematic (below). I don't seem to get a lot of difference varying the bias from 60 to 100mA.
http://www.pmillett.com/829b_amplifier.htm
From Pete
I'm running the 829B's at about 80mA, B+ of 320V, with cathode bias. For details look at the schematic (below). I don't seem to get a lot of difference varying the bias from 60 to 100mA.
I don't think I want to be running the 829Bs in triode mode - perhaps I'll use a depletion mode MOSFET front end and run parallel pentode mode, with Schade -style feedback. The big question is, what do I use for screen voltage? I understand that the screens are hooked together with a common bypass capacitor. I guess I can set the screen voltage by experiment, maybe starting at around 200V. An active shunt regulator would be a nice way to regulate the screen voltage. The grid bias will be by guess and by-golly as well.
This Mazda datasheet for the 829B contains data for use as an AF modulator in class AB1:
829B Mazda
According to this info by Mullard the value of the internal capacitor between the screen grids and cathode is 65 pF.
829B Mazda
According to this info by Mullard the value of the internal capacitor between the screen grids and cathode is 65 pF.
