Hi All,
I have been reading the notes on Flag/Pennant type antennas. I must say that
I have tried all three versions, the Flag, Pennant and the delta. For me the
Delta is the best of the lot.
With the Pennant and Flag types I could never achieve a reasonable F/B
ratio.
With the Delta, it seems to be in the 25 dB range (see below).
All three antennas were located in roughly the same area, a small yard
surrounded by a 6' chain link fence and about 100' from the transmitting
vertical. The vertical uses surface radials. I used the same matching
transformer (K6SE) and terminating resistor in all three antennas. The dirt
here is sand and rock ( Tucson, AZ)
The Delta was made rotatable using a cheap radio shack rotator. Using local
AM stations around 1600, I can see 25 dB or better F/B when rotating the
antenna. It is more difficult to determine the F/B on 160, but there is one.
I am using an old Ameco PT-2 preamp (which seems to have a preference for
amplifying the noise).
So far I am quite pleased with the Delta, it has a slightly lower noise
level than the vertical however, it is not even close to beverages I have
used in the past.
73, Art N4PT
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