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All wave and High efficiency antennas
EdHolland
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#6

03-24-2020, 03:23 PM
Ron - I've seen a few implementations while reading through the 1930's

One is to use an automotive spark plug, grounding the body, and connecting the antenna wire to the center electrode. The gap can be narrowed (a lot) although I have not seen this mentioned.

Another is to use a Neon bulb - they act quickly and have a striking voltage ~ 70 V. One of my newer receivers, made by Icom, has just such a feature, soldered directly to the antenna socket just inside the radio's chassis.

Still another is to use two stacks of fast recovery diodes, wired in opposite polarity across antenna and earth. Two or more are usual, allowing for higher real signal voltages before the diodes themselves cause spurious signals through intermodulation. Lots of modern comms receivers use this approach.

Quick google images search on the subject


P.S. Anything on All-Wave or High Efficiency Antennas?

Cheers,

Ed
I don't hold with furniture that talks.
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RE: All wave and High efficiency antennas - by EdHolland - 03-24-2020, 03:23 PM



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