Ultimate Crystal FM Radio/Receiver without Power Supply and Amplifying

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Some time ago I did a "regen" with a 12AU7 for FM, the trouble was the extraordinary sensitivity to my hands (very difficult to tune), but received OK in FM. Audio quality was good.
I don't talk about a FM front end with tubes. I talk about a VHF FM Xtal Set without any transistors and tubes, i. e. without any amplifying.

The audio amplifier for the demonstation video " FMxtalSetDemo03" from
FMxtalSetDemo03 - YouTube
is necessary only for youtube.
This showed device is the result from the first URL from post #1

Very interesting !!!

To find more informations here several keywords to feed "Google":
German:
UKW-Detektor UKW-Flankendetektor
Dutch:
FM Kristalontvanger
English (CO.UK, CO.AUS, NZLD, CDN, USA):
FM "Crystal radio" "VHF Crystal radio" "FM Xtal"
"Tuned Diode VHF Receivers"
"VHF (UKW/FM) slope detection"
Italian:
Ricevitore Cristallo FM

Please let me know the right keywords in other languages - thank you very much
 
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FM slope detection may net a few more hits, somehow though I can't imagine this approach is going to result in the ultimate in sound quality, although it certainly looks cool. :D

The discriminator version discussed in the link referenced looks very interesting, interesting enough that had I time I would probably give it a go..
 
I don't see the crystal...
Please note: "crystal" is here a colloquial term (for historical reasons)
for FM are diodes in use instead a crystal (Xtal) in those days for an AM detector.
Follow diodes are examples:
HSMS2850 (Surface Mount Zero Bias Schottky Detector Diodes)
http://www.crystal-radio.eu/hsms285xdata.pdf
Mullard GEX66
GEX 66, Tube GEX66; Röhre GEX 66 ID37010, Solid-State-Diode
BAT15-03W
http://www.freesoft.org/radar/Guardian/part2/bat15-03w.pdf

What are the colloquial term in your language in this matter?
 
We use both "crystal" and "detector". I remember when I was a young boy, I build a detector AM radio in a wooden box, with a silicium "crystal" and a needle touching it. It did not need any battery, and the output power was sufficient to listen to the local AM radio station via magnetic headphones... Putting the headphones in a dish, it was quite loud :)
 
We use both "crystal" and "detector". I remember when I was a young boy, I build a detector AM radio in a wooden box, with a silicium "crystal" and a needle touching it. It did not need any battery, and the output power was sufficient to listen to the local AM radio station via magnetic headphones... Putting the headphones in a dish, it was quite loud :)
That's also by me the first tasks in electronic.
by looking for informations in your country I have found this URL collection:
Galena Hasznos linkek :::::: Powered by: www.webtar.hu ::::::*
This thread I have start, because concerning FM you will find not so a wide range than concerning AM.

Now an off-topic question to you.
I need an email address from Nokia in Komárom, because I want to order a service manual from the sat receiver Mediamaster 9470S and 150S, both manufactured in Hungary. Perhaps you can find out for me - thank you very much for your efforts. The web address is
http://www.nokia.com/hu-hu/tamogatas/kapcsolat/
 
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