I got the switching properly sorted this weekend - I now have a choice
of up to 5 rx antennas, only got 4 at the moment.
1. the vertical used for transmit
2. A tuned loop with 2 turns, about 1 metre square with the centre about
9 feet high
3. A EWE pointing to the USA
4. The 80m dipole (which is fed with open wire, centre at 60 feet,
broadside to the USA) through a tuner
5. Waiting!
So far the EWE seems to do what it is supposed to, although the noise
is still bad. On it, the S/N on Bill, K0HA, was about the same as on the
dipole, but of course the signal was weaker. The signals from Eu were
much weaker. The loop still gave the best S/N. I'd suggest a tuned loop
is worth a try, especially if there is a definite source for the noise.
I'm wondering if a phasing system might help get the noise down. The
problem is, I think, that there are multiple noise sources.
I figured a possible route is to mix 160M up to VHF, use a phase shifter
consisting of cascaded 90 degree hybrids with varicap terminations, and
then mix down again ( using high dynamic range mixers, not NE602s!) This
would make the phasing sections practically small, so several parallel
paths could be incorporated to account for multiple sources. Has anyone
any comments to make on this approach?
73
Peter G3RZP
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