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Telamon · January 19th 07, 03:51 AM posted to rec.radio.shortwave

In article . com,
wrote:

I must be doing something wrong.

Frequency 6.486MHz (BTW arabic male)

I first tried 2 active dipoles seperated by 100' on a north to south
line. Next I tried a 50' wire 6' off the ground with a WinRadio
WR-LWA-0130 "long wire adpator, with either of the active dipoles,
then I ran another 50' at right angles for the first, also with a
WR-LWA-0130 and tried them all with my Mini Circuits ZFSC-2-1, that
while rated for 5~1000MHz operation has been tested and it works fine
down to well below 100KHz.

The nulls we less frequent but much deeper when they came.

I then used a 2nd R2000 and fed each receiver with different antennas
and just let the audio "mix" from the respective speaker outputs. The
active dipoles gave the best overall effect. There was a very
pronounced comb filter effect kind of like The Small Faces "Itchycoo
Park" from 1967, or Gobi Grant's "The Westward Wind".

Not too bad I think I will investigate some more this weekend.

At this point a couple of active dipoles into a broadband "phaser"
allow me to peak the signal and that works better the diveristy. Now
what would happen if I had 2 sets of active dipoles feeding seperate
phasers feeding seperate receivers?

I can get at the AGC in my R2000 fairly easily and it should be
fairly simple to build a comparator to pass the strongest signal to
the audio chain.

Just what I need another radio project.

For diversity reception you "switch" to the best signal instead of
mixing them together.

The best approach is two antennas with plus 1 wavelength between them
into two separate receivers and switch the audio between them based on a
decision circuit looking at both radios AGC voltage.

--
Telamon
Ventura, California