Wouldn't the 4CX5000 tend to have a larger filter capacitor, and thus
a bit more energy to dump, or is peak current the real concern? With
Rich's example of the 10 ohm glitch R in the SB-220, and assuming some
stray R in caps and chokes, you are still talking about a peak current
pulse on the order of 180 amps!! Seems like an awful lot of current. What
can the average plate choke withstand??
Mike, W4EF...........
----- Original Message -----
From: "Tom Rauch" <w8ji@akorn.net>
To: <amps@contesting.com>; "Ian White, G3SEK" <g3sek@ifwtech.com>
Sent: Monday, September 10, 2001 10:16 AM
Subject: Re: [AMPS] SB-1000 mods?
>
> > In any case, the glitch resistor is one of those components that needs
> > to be located in a cooling air stream.
> >
> > Any idea how to get hold of these resistors in small quantities at
> > reasonable prices? Now it's Monday, is somebody gonna call
> RCD?
>
> I'd suggest people check manufacturers. I'm sure many have stock
> components that will do.
>
> For example, Ameritron has a variety of globar resistors and also a
> 400 joule 13 watt dissipation 1500 volt 10 ohm resistor as a
> standard component. A series combination of 10 ohm resistors
> would be a fairly inexpensive solution.
>
> The resistance actually needs to be selected by the ruggedness of
> other components, not just by voltage. For example, a 4CX5000
> can take a big current whack compared to frail small tube like a
> 4CX800. With the 4CX5000, your biggest worry is other
> components like RF chokes and screen regulation systems.
>
> I don't think X ohms per volt is a good rule, although I suppose it is
> better than nothing.
>
>
> 73, Tom W8JI
> W8JI@contesting.com
>
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