There is a problem with this idea. Many of the handhelds which say they are
AM, actually work by 'slope detection' Essentially they are FM but receive
on the side of the signal, but relies upon a carrier being present. You
have to look long and hard to be sure you actually have a real AM detector
in such a radio. There are some.
-----Original Message-----
From: Bob Locher <locher@sonic.net>
To: towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Friday, December 05, 1997 3:27 PM
Subject: [TowerTalk] line noise
>As Dave Leeson points out, the ideal receiver to track noise is an AM
>VHF handheld.
>
>Of course, most hams have ready access to 2 meter FM transceivers, but
>these are nearly useless thanks to FM's inherent noise rejection.
>
>However, recent handhelds also include a receive capaility on the
>aviation bands. Aviation radios transmit on AM, not FM, so the
>transcievers automaticaly switch to AM reception in those bands.
>
>So if you are tracking a noise source, set your transciever to a
>frequency somewhere around 123 mHZ - any empty frequency within a mHz
>will be fine - and go hunting. Good luck.
>
>
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