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LF/MF
I am experimenting at present with antenna (space
diversity) using two loops. Loop A is 40 metres perimeter vertical
orientation, Loop B is 190 metres perimeter also vertical. Both loops
optimum E/W.
I am using two receivers in this experiment Ant A
to Siemens D2155 level meter, BW 20 Hz and vy stable, Ant B to Datong up
converter and IC746 250 Hz BW. Both audio outputs to soundcard/ARGO display
allowing 50 hz separation for observation.
Observing DI2AM at present and having calibrared
this signal on both RX outputs at a point in time, both signals are fairly
constant but more variations have been observed on Ant A - 40m loop, the signal
surges in strength and then fades down, whereas Ant B has a more constant output
with less fade.
More time is needed for a proper assessment and
DI2AM is also a strong signal. I would need a few long haul signals for a proper
test like Russian or USA .
Interested in MF signals at
present.
This method would also work with a couple of small
loops or a loop and probe type antenna, then at a glance one would know how each
was performing, of course with the loop in the optimum direction for target
signal.
This is just a simple setup, it works well and no
audio cross mod noticed, nice clean signals on display in spite of the fact that
the separation is only 50hz.
A nice balanced mixer would be a more sophisticated
approach, that might come later.
73 mal/g3kev
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