Michael Black wrote:
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.

In my days installing/maintaining FM receivers for background music (67 KHz
SCA subcarrier), I ran into that a few times. In one installation, I
installed our standard 3 element yagi on the roof and aimed it toward our
transmitter. I had line-of-sight to our transmitter some 30 miles away
(48.2 Km for our Canadian friend) but had horrible reception.
Our station was on 98.9 MHz (35KW), and at the top of the hill from my
receiving location (90° azimuth) , were 3 TV (Ch 4, 5 & 7) and 2 FM stations
(98.1 MHz & 100.7 MHz). I surmised the combined 716KW of those stations was
overloading the receiver. A dipole made from some lamp cord wire, stapled
to the ceiling of the room and fed into 75 ohm coax worked perfectly.
Sometimes simplest is bestest! :-)

Bryan WA7PRC