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Re: Today's LTAR

Could you pass that by us again--_real_ slow? The harmonic of a signal on
1680 is interfering with a signal on 850? Huh?

At first, I thought perhaps you meant that the local oscillator in your car
radio (tuned to 850) was running at 850 + 450 = 1300 (newer radios) or 850 +
455 = 1305 (older radios). A signal on 850 + 2*450 = 1750 (newer radios) or
850 + 2*455 = 1760 (older radios) would then cause the radio to produce an
"image" output when the radio was tuned to 850. However, this image would
probably be undetectable if your car radio had a tuned-RF front end
(preselector) as many car radios do to to eliminate such interference on AM.
The GE Super Radios also have a preselector on AM, but very few other
inexpensive portables do. Anyhow, this effect would occur if the pirate
signal were on 1750 or 1760, not on 1680.

Or are you saying the WEEI puts out a second harmonic on 1700 that is mixing
with the pirate signal on 1680. That's possible, but would not cause
interference as you tuned your radio in the neighborhood of 850. The mixing
products of 1700 and 1680 are at 20 kHz and 3380 kHz, neither of which
should affect your reception when the radio is tuned in the vicinity of 850.
Or are you saying that the 1680 signal puts out a _sub_harmonic at 840? What
_are_ you saying????


Dan Strassberg, dan.strassberg@worldnet.att.net
Phone: 1-617-558-4205, eFax: 1-707-215-6367

-----Original Message-----
From: Bob Nelson...WMWM <bobonradio@yahoo.com>
To: lglavin@lycos.com <lglavin@lycos.com>;
Date: Sunday, June 24, 2001 9:47 PM
Subject: Re: Today's LTAR

>Speaking of piratres, today I went to a wedding in
>Union Square, Somerville, and I had the Red Sox game
>on WEEI (850) as I drove. Heard some splatter on
>top of 850 as I got off I-93 and tried the harmonic,
>1700; sure enough, a foreign-language (Spanish?)
>with some sort of preacher. Also some sort of signal
>at 1680.
>The signal continued strong into Union Square. Talk
>about interference--listeners to WEEI in the area
>get it from the harmonic of this 1700 pirate.
>--- Laurence Glavin <lglavin@lycos.com> wrote:
>> The Jibguy today mentioned the AM/FM pirate "north
>> of Boston" on
>> 1670 and 88.3.
>Do You Yahoo!?
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