Well - I need to admit I was mistaken about how well my phased array
was working - and now have to agree with the experts that predicted
that my gamma matched tower was going to introduce a variable into
the equation.
I setup a monitoring antenna about 200 meters away from the two verticals
(one is a gamma matched tower - the other is a wire tee element). I
brought the coax into the shack and used a scope - triggered from some RF
from the transmitter. I was able to measure the relative phase delay
for each of the two elements (with the other one out of the picture) and
found that I had something around a 35 degree phase difference. It seemed
that the phase delay from the gamma matched tower was "less" than the wire
antenna. The absolute values are not important - since there are too
many variables like coax and path lengths involved.
I also seemed to notice a different amplitude - but I am now not sure
about those measurements as I see a lot of "QSB" on the readings - which
I am not sure I understand (could be the wind affecting my RX antenna).
At any rate - I did two things - added another 10 radials to the wire
antenna (I am now up to about 40 radials - which is getting close to the
number of radials on my gamma matched tower) - and I added 30 degrees of
coax to the gamma feed antenna.
I will be making lots of tests with this to see how it plays, but I did
get one encouraging report from ZL1KMN last night. I was sending him
"111 222 111 222 111 222..." and he said he could hear the 1s, but not
the 2s. Signals were not very strong and there was QSB - but this is an
encouraging sign. The 1s were end fire pretty much in his direction and
the 2s were off the back. I think I was hearing some F/B with the ZL
digi signal - but it is difficult to tell for sure as my noise level is
different between the two directions.
Europe was totally gone last night. Hope the band recovers tonight. I
did hear EL2DX coming up out of the noise - just around the time he QRTd.
CE1/K7CA continues to pump out a great signal and in addition to ZL1KMN,
ZL3IX and K9FD/KH6 were on the band.
73 Tree N6TR
Boring, OR
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