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Old July 17th 06, 07:31 PM posted to rec.radio.amateur.antenna
Dave Platt Dave Platt is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 464
Default Does anyone know of any AC (alternating current) 220V or 350V Shortwave Antenna circuits?

In article ,
Buck wrote:

There used to be radio antennas that plugged into the wall outlets.
They had a three pronged connector, but only one side was actually
electrically connected, the other prongs were plastic. I am not sure
what they did to isolate the electrical from the radio, but the
antenna used the house wiring for an antenna extension.

This may be what he is looking for, something that coupled with the
electrical wires for a longer antenna.


Ugh. Those things. "Turn your entire house into a gigantic
television antenna!"

These devices usually just couple one of the wires in the outlet to
the antenna lead, using a small high-voltage capacitor. Component
parts cost was a few cents, plus the cost of the plug, and (usually)
some intricately-shaped plastic case meant to make the device look
sophisticated. The case probably cost more than the guts, and the
advertised price was far greater than either.

From all I've heard, they generally gave poor performance for at least
two reasons:

- A house's power wiring is an excellent vehicle for RF noise and
hash... harmonics from power-supply rectifier, broadband impulse
noise from any AC motor with brushes, and so forth. Result: lots
of static in the picture.

- Multipath. The house wiring is of a complex shape, much larger
than a typical TV antenna. The TV or radio signal is likely to be
picked up by several different portions of the wiring, which will
mix (with varying amounts of time delay) at the coupler. Result:
a ghosty picture.

To paraphrase a Monty Python sketch concerning a particular Australian
table wine: "This is not a technology for using. This is a
technology for laying down and avoiding."

--
Dave Platt AE6EO
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