WE0H writes: Can you describe his loop and loop tuner box?
Hi All -
Now that I've sorted out my access to the Reflector I'll try
to describe what I'm using.
The loop is relatively small !! It's 9.5m wide by 3.5m high
and 1.5m off the ground. Its made from satellite downlead
coax (braid and foil type) and has a dc resistance of about
0.3 ohms. Initial measurements (using a step down toroid
transformer) indicated an rf impedance of less than one ohm.
Taking a close look at the map shows that the loop
horizontals are lined up 25 degrees off north so I guess the
nulls are on bearings of 115 & 295. QTH is Watford.
Transmissions on Sunday used the transformer and a series 34
nF which gave 10 amps loop current. I've since changed the
transformer for an L-match (8 micro Henries and 27 nF) to
match the 50 ohm feeder to the one ohm load. I now have 13
amps from the 90 watts coming out of the feeder.
BTW - the 90 watts is from a LINEAR amplifier so can run
PSK31. So far, only LF PSK contacts have been with Jim
(M0BMU) and John (G0NVZ). Is anyone else able to run 136 kHz
PSK ?
Brian
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