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Philco 80 Jr, just starting....
#14

Transient peak plate current! Icon_clap

As the source voltage goes up or as you increase the capacitance in a capacitive input filter you have to increase the plate source impedance or you risk exceeding the transient peak plate current and the tube striking an arc and making a bad mess of things. (end of tube, cap and xformer)

I now recall a Majestic cathedral and an experiment with a 47uF 450 V cap that ended quite badly. Icon_redface


Now I'm gonna have a beer and kill off that brain cell for good.

John
Las Vegas, NV USA


Messages In This Thread
Philco 80 Jr, just starting.... - by morzh - 01-28-2012, 09:35 PM
RE: Philco 80 Jr, just starting.... - by morzh - 02-29-2012, 12:21 AM
RE: Philco 80 Jr, just starting.... - by morzh - 03-15-2012, 12:05 AM
RE: Philco 80 Jr, just starting.... - by codefox1 - 03-15-2012, 01:25 AM
RE: Philco 80 Jr, just starting.... - by morzh - 03-15-2012, 10:44 AM
RE: Philco 80 Jr, just starting.... - by codefox1 - 03-15-2012, 12:20 PM
RE: Philco 80 Jr, just starting.... - by morzh - 03-17-2012, 01:14 AM
RE: Philco 80 Jr, just starting.... - by morzh - 03-21-2012, 03:35 PM
RE: Philco 80 Jr, just starting.... - by morzh - 03-21-2012, 11:03 PM
RE: Philco 80 Jr, just starting.... - by morzh - 03-21-2012, 10:56 PM
Re: Philco 80 Jr, just starting.... - by morzh - 01-29-2012, 03:24 PM
Re: Philco 80 Jr, just starting.... - by morzh - 02-05-2012, 06:23 PM
Re: Philco 80 Jr, just starting.... - by morzh - 02-06-2012, 06:31 PM
Re: Philco 80 Jr, just starting.... - by morzh - 02-11-2012, 08:25 PM
Re: Philco 80 Jr, just starting.... - by codefox1 - 02-11-2012, 09:50 PM
Re: Philco 80 Jr, just starting.... - by morzh - 02-12-2012, 11:14 PM
Re: Philco 80 Jr, just starting.... - by LASJayhawk - 02-13-2012, 02:33 AM
Re: Philco 80 Jr, just starting.... - by codefox1 - 02-13-2012, 04:22 PM
Re: Philco 80 Jr, just starting.... - by morzh - 02-13-2012, 06:37 PM
Re: Philco 80 Jr, just starting.... - by morzh - 02-15-2012, 12:50 PM



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