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Jeff Liebermann Jeff Liebermann is offline
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Default Interference in FM radio reception.

On Sat, 07 Jan 2012 01:19:27 -0500, micky
wrote:

There are two big ham radio clubs around here, and smaller ones in
adjacent counties.


The hams can be very helpful if properly approached. Much depends on
the available time, talent, experience, and hardware.

BTW, the two stations I mentioned are HD, so Jeff, maybe that's why
they get the noise. So is 88.1, which is very close to 88.5 of
course, but 88.1 is a local station, not 45 miles away, so maybe its
signal is too strong for this interference to interfere????


I can't tell from here. The problem is that the occupied bandwidth of
an FM station with HD1 and HD2 sub-carriers is more than the assigned
bandwidth:
http://www.ham-radio.com/k6sti/hdrsn.htm
Just read the first two sections, as the rest is all about fixing the
resultant noise.

Reminder: Please make an MP3 sound clip of the noises.
http://www.dxzone.com/catalog/Internet_and_Radio/Sounds/

Identifying Sources of Radio Frequency Interference Around the Home
"http://randombio.com/interference.html"

Hint: Assumption is the mother of all screwups. Test your theories
and guesswork, even if you think it's improbable. I've been wrong and
surprised more times than I can comfortably admit. That's one reason
my domain is called LearnByDestroying.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558