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THE AM BULLETIN BOARD => Technical Forum => Topic started by: WA4WAX on February 07, 2023, 05:54:57 PM



Title: FET Infinite impedance detector
Post by: WA4WAX on February 07, 2023, 05:54:57 PM
A tidbit sent to me on Twitter.

https://baltic-lab.com/2023/02/jfet-based-infinite-impedance-detector-for-am-demodulation/


Title: Re: FET Infinite impedance detector
Post by: W1DAN on February 10, 2023, 09:09:23 PM
Hi:

Nice article. Taken from a 1970's ARRL Handbook I used an infinite impedance detector using an MPF102 in an HRO I solid-stated. Worked fabulously, and I enjoyed hearing the different sound qualities of the tropical shortwave transmitters at 5MHz.

Funny no one else is interested in this simple circuit.

Dan


Title: Re: FET Infinite impedance detector
Post by: K9MB on February 12, 2023, 08:31:48 PM
Hi:

Nice article. Taken from a 1970's ARRL Handbook I used an infinite impedance detector using an MPF102 in an HRO I solid-stated. Worked fabulously, and I enjoyed hearing the different sound qualities of the tropical shortwave transmitters at 5MHz.

Funny no one else is interested in this simple circuit.

Dan

Nice call, Dan.
Here it is on page 229 of the 1972 ARRL Handbook.
Nothing new under the Sun, even the venerable infinite impedance detector adapted to a JFET. New one over 50 now…😉
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands