Re: Simulcasting on the same frequency

[SteveOrdinetz <steveord@xtdl.com>]

At 03:35 AM 6/18/97 +0000, you wrote:
> 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.


I worked at Wang Labs in the early 70s at the Tewksbury plant, and WLLH was
totally unlistenable there.  Dunno if it was right where the 2 carriers
intersected or what, but the signal was very distorted and phase-cancelly.
At the time I'd never heard of sync transmitters, and wondered why a station
so close had such a crappy signal.  Wrote it off as being a rinky-dink outfit.

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