Detection of Enemy Listeners. (Radio)

Hello,

Idea:

  1. Place radio transmitter somewhere on earth, send out signals.

  1. Place radio receivers somewhere on earth, receive signals.

  2. Measure differences in transmitted and received signals.

If enemy listeners are in between and are picking up the radio signal, the radio signal will weaken a bit.

Bye, Skybuck.

P.S.: Eat that dutch-science-show puhuhuhuhuhuhuh :)

Reply to
Skybuck Flying
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Oops, SkyDuck. You can't patent the idea now.

Reply to
krw

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

Reply to
Robert Baer

First, worry about all your enemies here on Usenet.

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Paul Hovnanian     mailto:Paul@Hovnanian.com
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Reply to
Paul Hovnanian P.E.

e

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

Reply to
Alien8752

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.

Q
Reply to
Q

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.

Reply to
Archimedes' Lever

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

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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.

Q
Reply to
Q

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

Best regards, Spehro Pefhany

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"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
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Reply to
Spehro Pefhany

:-) :-)

Reply to
Q

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

Reply to
ingvald44

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

Reply to
Q

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

Sylvia.

Reply to
Sylvia Else

I read them.

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

Bye, Skybuck.

Reply to
Skybuck Flying

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

X.

Reply to
Ximinez

Is radio the same as radar ?

Hmmm...

Bye, Skybuck.

Reply to
Skybuck Flying

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

Reply to
Jasen Betts

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