Hi,
I added another 90microH mounted orthogonally to the existing (also 90microH)
when modifying my 30S-1 for 160m.
The unmofidied amp calls for 1.5nF 6KV bypass after the (original) RF choke.
I mounted 5nF 10KV after the second choke and I was going to switch the 1.5nF
(now between the chokes) in and out of the circuit when going from the regular
bands to 160m.
Well it turns out I don't need to, and with it in place I still get about 10%
extra output on 160m, so that's one less thing I need to worry about. I have
the amp on the air for many hours with no signs of heating or fireworks.
Why am I even bothering with the second choke? However the numbers say I show
use it.
If the PA output has a (magnitude) Z of about 5-6K, and the choke and bypass
reactances are about j1000 and -j100 at 2MHz respectively, why shouldn't I
observe a lower efficiency output on 160m, instead I get more! What gives?
thanks for any inputs on this surprising output (pun intended).....
73s
kb3bf chris
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