Re: Simulcasting on the same frequency

[Dan Strassberg <dan.strassberg@worldnet.att.net>]

At 11:58 PM 6/17/97 +0000, you wrote:
>Maybe some of you who are more technically oriented can answer this question:
>
>What would happen if two AM stations in close proximity at the same frequency
>simulcasted?  Would it improve the reach of the stations?  Would they still
>cause interference on the margins?  
>
>For example, WPOR in Portland is on 1490 and there is a station in Augusta,
>about sixty miles north, on 1490.  The signals nearly overlap during the day.
> What would happen if they were hooked together and ran the same programming?
> A similiar situation exists at 1400 with WIDE Biddeford and WTVL Waterville.
>
In the case of the stations you name, it would work fine, because the
coverage really doesn't overlap. Down here we have WLLH (1400) which has two
synchronous transmitters, one in Lowell, the other in Lawrence, ten miles or
so away (someone will post the exact distance, I'm sure). The coverage
overlaps severely and the station used to synchronize the carriers within
about 0.1 Hz to minimize the beat-frequency effect between them. Although
WLLH may have actually sent the carrier between the sites via coaxial cable
at one time, I believe that for many years, the "synchronization" was
accomplished simply by using extremely well-matched crystals. Lately, the
carriers have drifted apart and nobody seems to be doing anything about it.
When the carriers are not well synchronized and you're in an area where the
neither signal is much stronger than the other, the result is a signal that
only a DX enthusiast would be likely to tolerate.

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Dan Strassberg (Note: Address is CASE SENSITIVE!)
ALL _LOWER_ CASE!!!--> dan.strassberg@worldnet.att.net
(617) 558-4205; Fax (617) 928-4205

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