On 10/1/2013 7:51 AM, Richards wrote:
These receive only antennas are nice to have, but I figure it is
better to improve one's transmit antennas if possible - especially if
one can can replace them with antennas with more gain.
RX-only antennas are most useful on bands where it is impractical or
expensive to get directivity from your TX antenna -- 160, 80, 60, 40,
and 30.
Another VERY important point. Contrary to manufacturers' claims, it is
VERY difficult to get much more than about 5 dB gain over a dipole with
a collection of aluminum on a boom. That was the clear result of
extensive measurements by N0AX and K7LXC of a dozen or so of a broad
selection of tri-banders. An M-squared C3 was the best of the small
ones, with an average gain of 3.4 dB across the three bands. A Mosley
TA33 was only 1.6 dB (loss in the traps made the difference). An
M-squared C-31XR (31 ft boom) was the best of the big ones with 5.3 dB
over a dipole, a Cushcraft X9 was 5dB, a Bencher Skyhawk was 4.4 dB, the
rest were less than 4 dB, and several big Mosley antennas had negative
gain!
73, Jim K9YC
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