[Amps] Use of Manual T/R Switches

[Tom Rauch]

----- Original Message -----
From: "k7fm" <k7fm at teleport.com>
To: <W0YR at aol.com>; <amps at contesting.com>
Sent: Thursday, March 06, 2003 9:22 AM
Subject: Re: [Amps] Use of Manual T/R Switches


> The T/R switch can be a point of concern, as you pointed out.  The problem
> with a knife switch, however, is after the operator has had too much
Corona.


What I used to do was hang my feedlines down from the top of a plywood board
nailed to the wall. The board was covered with thin copper foil. The shields
were connected to the copper by wood screws.

My main feeder from THE AMPLIFIER had a foot long braid, and it was screwed
to the copper.

I bent a hook in the center conductors of each cable, and would simply let
gravity make the connection. To change feeders, I just lifted the coax and
hooked it on another antenna line. If there was a poor connection, THE
AMPLIFIER (as opposed to "amplifier") would weld the cables. To release them
it only a sharp twist and a tug, or a ping with a small hammer.

I was never able to get this system to work well on QSK, so I used a pair of
10 watt 250 volt lightbulbs as a series limiter (they lit like flashbulbs,
and doubled as a reminder the power was on) and a 6AL5 tube as a clamp for
the receiver, followed by a 6J6 to make up for gain loss.

I'm actually serious about this, I used this system for years as an antenna
and TR switch. It worked quite well.

73 Tom