Philco 80 Jr, just starting....
Posts: 289
Threads: 40
Joined: Oct 2011
City: Las Vegas, NV
Transient peak plate current! 
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. 
Now I'm gonna have a beer and kill off that brain cell for good.
John
Las Vegas, NV USA
Messages In This Thread
Re: Philco 80 Jr, just starting.... - by LASJayhawk - 02-13-2012, 02:33 AM
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