"Bruce Wilson" ) writes:
http://en.wikipedia.org/wiki/CONELRAD

In doing some research on Civil Defense I ran across the CONELRAD stations.
In Wikipedia's entry there is a statement that hams were required in 1957
and later (presumably until 1963 at least) to check that a major broadcast
station was on the air.

Any old-timers remember this requirement? Was it regularly done by working
hams?

There was a such a law in the US, though since it was before my time (and
I'm not in the US), I've forgotten the details from when I read the
old magazines.

But for at least some of that period, US hams were supposed to monitor
the AM band to make sure that there was no Conelrad alert, because if
there was they were supposed to go off the air.

The ham magazines at the time were full of construction articles to
deal with this. In a Conelrad emergency, commercial broadcast stations
were supposed to go off the air, with emergency stations coming on at
specific frequencies. So there were lots of little adaptors to connect
to AM radios to either make sure the usual station was still on the air, or
to make sure the emergency frequency was still empty (I forget which
was tested for, and maybe it was on the whim of the individual). These
automated schemes meant the hams didn't have to actually listen to the
stations to see if they were still on the air, which would have caused
problems when transmitting with a microphone since you couldn't retransmit
a broadcast station over ham frequencies.

Michael