<bryan@blackballclub.com>
>
> They were receiving me strength five, but for much
> of the transit I could not hear them at all.
>
Antennas work by the rule of reciprocity, and above indicates antenna
is not the problem, at least in that azimuth of the 360-deg pattern.
> In both cases I have been able to hear other
> aircraft speaking to them strength five,
If you can't hear a ground station, but other A/C yes, and they're not
in the same general azimuth, the radiating pattern of the antenna is
suspect -- an installation location problem. A/C to A/C doesn't have
the line-of-sight problem like A/C to ground over terrain. But the
ground station can achieve a near perfect antenna, canceling out the
line-of-sight issue.
> I can now see that I have a common problem at the lower frequencies,
Receive problems on the extremes of the bands indicate alignment
problems, but radios just don't go out of alignment to any significant
degree, if at all. The degree of problem you report suggests a
component might be way off spec. Low odds, but people hit lotteries.
Also, radiating pattern problems can be frequency dependent to some
degree.
Hope this helps rather than chases wild geese!
BTW, we can't deduce strength five or strength anything from what is
heard, unless rather weak. Leveling circuitry in modern radios +
other factors. Our old control tower was even handing "strength
three" or "four" to people. Must have an S-meter I figure. But first
visit to the tower, I alarmingly saw they used a Genave Alpha 360, a
"doorstop" in alternative use. No S-meter, but that turkey of a radio
could actually hint at strength reasonably well.
Reg,
Fred F.
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