Hi All,
I have been playing with the terminations on the "Delta" rx antenna. By
various means I have come to the following for my system:
Termination Band
700 Ohms 160
850 Ohms 80
1156 Ohms 40
Given the above I chose a 750 ohm termination, I split the difference
between 160 and 80 meters (who needs 40?).
Also, I have a shielded coax loop as per the http://www.qsl.net/kc2tx/ site.
It is interesting to note that the "Delta" rx antenna shows a lower noise
level than the shielded loop(quiet conditions no QRN). On a clear frequency
on 160 the "Delta" shows s0 and the shielded loop shows s3 to s6. On rx
signals they show about the same signal strength through the preamp (Fixed
gain through the PT-2), about 10 db down from the short vertical tx antenna.
Bottom line, the "Delta" presents signals at a readable level with little to
no background noise, the shielded loop has a very noticeable noise level and
the short vertical has a noise level that is much louder than the rx signal.
On the "Delta" the signals pop up out of what sounds like a dead receiver
(the S-meter never moves from 0). I can copy signals on the "Delta" signals
that are at the ESP level to no copy with the shielded loop or the short
vertical. This is all based on East Coast stations (the beacon W8JI and
others) from my QTH in AZ.
The rotor on the "Delta" is probably a waste since the beamwidth is so
broad. It would seem that N, E, W and S are the only necessary directions. I
other words big direction lumps. From my QTH that means East at night and
West in the morning. The rotor is getting bored.
All these observations are with the current conditions and of course
conditions could change and change all of the above.
I know this is all very subjective but in the absence of exotic test
equipment it is the best I can do.
If the band would improve I might actually hear some DX signals.
73, Art N4PT
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