Re: [IRCA] FCC Enforcement Priorities (Fwd from: Broadcast)

["Craig Healy" <bubba@xxxxxxxxxxxxxxxxxxxx>]

> I once thought about building an alarm system to let me know if one of
> my locals went off the air.  This was back before personal computers, so
> my idea involved a box full of transistor radios, each hooked to a
> detector that would let me know when there wasn't any audio present.  I
> never got around building it, but it would have been an interesting
project.

Crystal radio and DC amplifier?  Shouldn't be too difficult to make
something that will hear a high signal strength station and drop out after a
minute or two if it vanishes.  You could even leave a radio and cassette
deck connected so the recording starts/stops with carrier sense.  No need to
even wake up.

Too bad the old Conelrad radios are long-vanished.  That worked on carrier
sense and had relay outputs.

> Nowadays, we have PC controlled radios, which wouldn't be hard to set up
> for this purpose.  Have it scan through each local or semi-local pest
> and compare the signal level to a predetermined threshold.  If the
> signal level is too low after a couple of scans, have it sound the alarm.

Too complicated.  You could even find an old radio and locate the AGC
circuit.  Amplify that to a relay coil.  Station drops, AGC level changes,
and the relay changes state to trip an alarm of recorder.

Craig Healy
Providence, RI



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