"Paul Van House" wrote in message
...
In article , says...
In article , (Gene Seibel)
wrote:
Do you remember what the specific requirements were back in the days of
conelrad?
If we're talking FM stations, I don't know for sure but I think the
FMers (what few there were) would have had to sign off. The
participating am stations all switched to one of two frequencies (1 high
or 1 low) theoretically to confuse enemy "signal tracers" from seeking
and destroying transmitters.
640 and 1240. Local areas or markets had stations assigned to one of the
two, and they would cycle on or off to further confuse RDF usage of signals.
The entire national system was tested several times in the early 60's, with
nothing on any channel except 640 and 1240 for a half-hour around 11 AM on a
weekday.