On Mon, 15 Mar 2010 17:17:14 -0400, mm wrote:
I have an clock radio about 30 years old that, when tuning for 88.5
FM, for example, by turning the dial, will find that station, and then
a little higher will be another station, and a little higher still
will be 88.5 again, often a stronger signal than the first one.

I'm sure it's not a second station playing the same stuff.

Well, at 30 years, it sure ain't digitally tuned!

The variable capacitor that you tune the radio with is going to full
capacitance (lowest frequency) _before_ it reaches the physical stop.
Ergo, once you go past full capacitance and approach the physical stop,
you will be tuning back _up_ in frequency again -- all be it for just
a short range...

Too, with the age of the radio, 'things' have changed and undoubtedly
the alignment has shifted to exacerbate the effect you see.

Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
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