[Amps] Using door knob caps as padders/blockers

[Phil Clements]

> First, Ameritron does not use mica's in the tank of higher power
> amplifiers. Never has, probably never will.
>
> They switched to ceramic chip capacitors because the doorknobs they
> had used for years suddenly failed to meet temperature vs capacitance
> change ratings when HEC starting using tooling or materials purchased
> from ITT-Jennings.

I stand corrected, everyone!
I thought the Ameritron caps were mica...my mistake.

I do know that every SB-1000 I have tuned up on 160 meters
has the same drift problem. I have cured that problem on several
occasions with the Ameritron CERAMIC chip caps. With
a single 3-500Z, voltage is not a problem in the loading
section of a PI-L tank as it would be with a legal-limit amp.
They seem to be adequate. I see that the AL-1500 used 500pf
door knobs . Do they still do? Has anyone out there experienced
padder drift on 160 meters with an AL-1500?

(((73)))
Phil, K5PC