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Old April 4th 07, 04:23 PM posted to rec.radio.amateur.antenna
Michael Black Michael Black is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 322
Default Non technical antenna question

"Larry Gauthier \" ) writes:

If you find yourself with two radios that are similarly-equipped in terms of
antennas, but one gets your favorite stations while the other does not, then
the one that does not is either broken or has designed-in lousy sensitivity.

Actually, it might be the reverse, depending on what exactly is happening.

I have a all in one stereo I got at a garage sale. It had lousy reception of
a non-local station that is always receivable here on other radios, even lousy
ones. I naturally thought the antenna was the problem. But I did something
and realized I likely was attenuating the signal, and the issue wasn't
"not enough antenna" but too much. I took off the whip antenna, and that
thing gets perfect reception on that non-local station, whereas before it
was noisy.

Clearly, the stereo was being overloaded by local signals, which impacted
on it's ability to receive the strong but comparatively weaker non-local
station. Removing the antenna attenuated the local station(s) enough that
the stereo didn't overload, but the non-local station was still strong
enough to be received fine.

Most consumer broadcast receivers are too sensitive if anything, because
they don't handle strong signals that well, yet the strong signals
overloading them make them useless for receiving distant signals. A
less sensitive receiver wouldn't be as good for distant reception, but
the local signals wouldn't mask those distant signals with overload.

I don't know if this is the case here, but it is worth looking into
since it's the last thing people generally expect. I notice when I
got a Grundig portable sw receiver at a rummage sale in September, the
manual specifically states to keep the whip antenna shorter when on
the FM broadcast band (the antenna being longer for the shortwave
bands), and having been prompted by the manual and experience, I do
notice that not so great reception on the FM band is improved when
I shorten the whip antenna.

Michael VE2BVW