Quote:
Originally Posted by cameronflyer
I finally got my capacitor ballast built . . . . .
I do have a question though. I used 20watt resistors on the rectifier side of the ballast and they are running warmer than I expected. Not to warm for a 20watt but warmer than I thought it should be. I should ad that I used a CL90 from the ACline to the ballast and she is drawing .8 amps roughly at 115v AC on the line
|
Congratulations! Most 8BP4's went gassy and developed a brown center spot.
Sam's 83-6 says "RATING: .9 Amp at 117 Volts AC" so you are quite close. I'd have estimated a little bigger draw if you have not yet replaced all the small capacitors, especially the plate to grid ones.
Re: Heat from B+ current limiting resistor.
Well, remember the wires in a normal ballast glow red hot and that was the reason for the little square of asbestos that was in side the cabinet over the ballast.
I'd sure keep that resistor above chassis in an old ballast shell and the filament capacitors safely under the chassis away from the hot resistor(s).
Jas.