>Well, I have some problems with the premise that the KT34XA traps have that
>much internal resistance that there is significant heating under rf load...
It's really not that hard to understand. Let's boil down the math for a
simple loss budget for a connection made with a ham-type UHF connector.
Loss per connector = 0.05 dB (doesn't seem like much, eh?)
Total loss = 0.10 dB (who even counts this stuff, right?)
1500 W * 0.10 dB =
1500 W * (1 - 10 ^ (.01)) =
1500 W * .0233 =
That's right. For every connector pair, you lose 35 watts.
A 0.3 dB loss in a switch subtracts 107 watts from your ability to break a
And for every 1 dB of loss in your feedline you squander 388 watts.
(So much for the guys who say, "Oh, RG-8 is essentially lossless at HF.")
Assuming that the connections to a typical trap combined with ohmic
resistance has the same miniscule 0.1 dB loss as a connector pair, it's
essentially a 35W heating element. No need to climb the tower. Just turn a
35W bulb on for a while, then grab it tight to simulate this experience in
the comfort of your living room!
For a safer thrill, add up a loss budget for your station and see how little
of your power is actually reaching those expensive antennas.
Rob Hummel (WS1A) <email@example.com>