Detection of Enemy Listeners. (Radio)

Oops, SkyDuck. You can't patent the idea now.

If you had a brain, you would know how to think.

First, worry about all your enemies here on Usenet.

-- Paul Hovnanian mailto: snipped-for-privacy@Hovnanian.com

------------------------------------------------------------------ The Three Laws of Thermodynamics: 1) You can't win. 2) You can't break even. 3) You can't quit the game.

Absolute best-give-you-the-benefit-of-the-doubt-case, you are sending microwatts, the listener(s) use crystal sets, the Earth/ atmosphere/ionosphere has exactly zero loss at the frequency used, you MIGHT detect some weakening of signal strength if there are many, many listeners. And of course they don't have to be "between" your transmitter and detectors.

In Real Life any "power absorption" will be swamped by other effects.

Oh no, you're trying to refute a _TV show_?

Mark L. Fergerson

You can't distinguish between a piece of wire and an enemy listener, more general, how do you distinguish beween multipath and an "enemy" listener? You can't.

The best way to search for a listening radio is still to receive the few milliwatts emitted by its local oscillator. This is the method used by the police to capture radar indicators. (fuzz busters)

But what you can do is to simply listen with a receiver to a transmitter to find multipath features in the signal. Any change in multipath is indicative for a reflector moving between the transmitter and the receiver. This experiment is easy, tune your TV set to a distant weak station and watch for the ghost images on the screen, if an commercial aircraft passes then you'll see that the ghost images wiggle. Actually you're seeing the direct signal from the station including a mirror image going from the transmitter, reflecting to the aircraft arriving at your aerial.

There are no cops running around with detection gear looking for radar detectors. Such devices would be prohibitively expensive.

In states where it is not legal to use one, it is still legal to own it, and STOW it in your car. If, however, it is in an "installed location" it doesn't matter if you claim it was turned off or not, you'll get cited, and it will get confiscated.

RDD's are not cheap but they are real and some law enforcement agencies really use them:

It is not very difficult to detect a local oscillator, you can hear a 1 milliwatt transmitter as well as you can see a 1 milliwatt LED. Shouldn't be a problem up to a few hundred meter I guess.

One way to detect radar detectors is to flip the radar on and see if any brake lights come on. ;-)

Best regards, Spehro Pefhany

:-) :-)

The more folks who read a stupid usenet posting the dimmer the typeface becomes..

Meanwhile there have been a dozen responses, but Skybuck Flying, the OP, didn't react to any of them.

That's why I keep a TRF receiver handy for all my clandestine listening needs.

Sylvia.

I read them.

However yours didn't come through for some reason... but it's on google ;)

Bye, Skybuck.

Yeah, he's Dutch. But we're not really proud of that fact.

X.

Is radio the same as radar ?

Hmmm...

Bye, Skybuck.

no, radio has sound, radar has pictures, but crap sound.