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Author Topic: UHF Crystal Radio  (Read 1022 times)

Offline vu2nan

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  • Nandu - VU2NAN since 1977.
    • Amateur Radio VU2NAN - Nandu
UHF Crystal Radio
« on: December 26, 2015, 13:14:52 UTC »

Offline GM0LVI

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Re: UHF Crystal Radio
« Reply #1 on: December 26, 2015, 19:17:36 UTC »
Very ingenious Nandu!!!
Dave

Offline vu2nan

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Re: UHF Crystal Radio
« Reply #2 on: December 27, 2015, 02:20:39 UTC »
Thanks, OM Dave!

73,

Nandu.

Offline vu2nan

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Re: UHF Crystal Radio
« Reply #3 on: January 06, 2016, 14:20:20 UTC »

Offline vu2nan

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  • Nandu - VU2NAN since 1977.
    • Amateur Radio VU2NAN - Nandu
Re: UHF Crystal Radio
« Reply #4 on: January 20, 2016, 06:28:40 UTC »
Another update.

A folded dipole version, mounted on a terminal block.

It obviates the need for a coil / additional diode and works quite well too.

Regards,

Nandu.

Offline vu2nan

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  • Nandu - VU2NAN since 1977.
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Re: UHF Crystal Radio
« Reply #5 on: January 23, 2016, 18:31:13 UTC »
Yet another!

The terminal block arrangement made it convenient to replace the folded dipole with a full wave loop.

Likewise with an AWX antenna.

Results were as good as with the folded dipole.

73,

Nandu.

Offline vu2nan

  • Warrant Officer Class One
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  • Posts: 45
  • Country: in
  • Nandu - VU2NAN since 1977.
    • Amateur Radio VU2NAN - Nandu
Re: UHF Crystal Radio
« Reply #6 on: January 30, 2016, 17:55:38 UTC »
The latest update!

A second Yagi Beam was then rigged up, with another diode providing the return path for the audio, instead of the coil.

The signal strength was not as good. During trials, a chance shorting of the second diode gave a considerable increase in signal strength.

The diode and capacitor were hence discarded. Performance of this single-diode UHF crystal radio is quite good.

73,

Nandu.