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Phil Allison[_3_] Phil Allison[_3_] is offline
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Default How can the same FM station appear at two different spots on the dial?

micky wrote:

How can the same FM station appear at two different spots on the dial?

Where I live there are two FM radio stations, 88.1 which is only a few
miles away, and 88.5 which is 40 or 50 miles away.

Right now, only my expensive KLM radio plus any car radio gets the
second one well, but I've had some cheap radios that do almost as well.

I lose track of which radios those are, so I'll start tuning at 88.1 and
tune up very gradually. After a period of silence, when I get above
88.5 to what I'd estimate is 88.6 or .7 or .8 I get 88.1 again.



** What make and model radio is doing this ??

Does it have a TDA7000 IC inside, by any chance ??

Those have an internal IF frequency of only 70KHz and image rejection is by purest magic.

FYI:

If this problem exists on only one radio, it must be the fault of that radio.

FYI 2

Your post is 99% incomprehensible drivel.



.... Phil









How is that happening? I know about harmonics, but that doesn't apply,
does it?



P.S. This means 88.5 doesn't come in at all. I've tried stretching
out the power cord, which on the cheap radios is usually the antenna.
Sometimes that helps but on most of the radios, 88.5 won't come in at
all.

P.P.S. 88.1 is WYPR Baltimore. 88.5 is WAMU in DC. Sometimes they
play the same thing, like during the top of the hour news, Diane Rehm,
etc. although WAMU is on a 5 or 10 second delay most of the time.
Because the topic and the voices can be the same it means I can't tell
for a while if I've gotten 88.5 or just another 'instance' of 88.1.