> On another subject. Tom, W8JI, would a resistive shunt solve some of
> these amplifier stability problems? On a Ten Tec 30 meter QRP rig I
> installed a 150 ohm resistor across the antenna terminals to stop an
> oscillation around 8 MHz. The resistor value could have been much
> higher but I wanted lots of margin and am willing to burn a couple of
> dB of signal during casual QRP operation.
The problem is no one wants to burn a couple dB at 500-1500 watts,
and even if you did where would you put the heat??
On VHF amps I use diplexers (as are also used for mixers). It is
always possible to use a diplexer, but just keeping the impedance low
also works in many cases.
I'll eventually put something up in great detail, after I collect
more info on the problems people had in the SP.
73, Tom W8JI
W8JI@contesting.com
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