[Amps] Placement of plate r-f choke bypass capacitor

[Bill, W6WRT]

ORIGINAL MESSAGE:

On Mon, 15 Mar 2010 21:23:05 -0400, "David J Windisch"
<davidjw at cinci.rr.com> wrote:

>The h-f amplifier designs with which I'm familiar usually have the plate r-f choke bypass capacitor placed as close as possible to the cold end of the choke.

REPLY:

You also want the cap as close as possible to the (grounded) grid of
the tube, which is the common return point for the RF being bypassed. 

Having the ground point 11 inches away is asking for trouble. That
means that 11 inches of the chassis is "hot" for RF. Ten-Tec is
apparently getting away with it, but that's a risky business.

Where this might cause trouble for example, would be if the grid-trip
circuit was mounted somewhere in the 11 inches, or if the input
circuit had a ground connection there. Not good.

73, Bill W6WRT