Use a Schottky diode.
BAT 85 or any replacement will do perfectly.
will work from 0.17 volts, even lower as an germanium diode, made a bunch of these radio's last year for the Jota Scouting kids.
;)
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Use a Schottky diode.
BAT 85 or any replacement will do perfectly.
will work from 0.17 volts, even lower as an germanium diode, made a bunch of these radio's last year for the Jota Scouting kids.
;)
You could use a germanium transistor with no bias resistor as a detector, instead of the 1N34. But Germanium anything is a little hard to find.
Old junk radios, especially early transistor types might have 'em. I remember using RF probes on VTVM's that had tube on the end of a (warm) stick, basically.
I did find a cool kit site, http://theinspireproject.org/index.p..._receiver_kits
Sound-card shenanigans... http://www.qsl.net/dl4yhf/vlf_rcvr.html
Don't the Schottky diodes work best in the higher frequencies?
They work fine up to the Ghz area depending on the type you chose.
The BAT 85 ( still 700 left) worked fine for the Jota as detector diode for the AM radio the kids build, i had some OA 85, AA119 ( germanium ones) to compare to, and the Schottky BAT 85 worked better.
If anyone needs original BAT 85 Schottky diodes from Phillips i got some for free.
I normally use them to replace the noisy switching diodes in the bandpass filters.
Just for Island members, QRZ need not reply.:mrgreen:
I'd only played with them in the VHF region... cheap way to listen to airplanes. :yes:
Bought a box containing 1000 original Phillips BAT 85 Schottky diodes for a few Euro's from a nincompoop on a hamfair, which did not know what they were.
Good for me ;)
So, if anyone here needs a few just PM me, or put in a request and i'll pop some over in the mail.
Did that lots of times from Australia to the US and Canada, Indonesia, and Asia.
Don't think i'll use up the remaining 700 in the 20 - 30 years i have left ;)
Sound like something interesting to play with. wonder how good they would work as the AM or SSB balanced detector in an old CB.Quote:
Originally Posted by PA5COR
Quote:
Galena is a natural semiconductor and so the forerunner, the enabler, of all the electronic gadgets we have today, from telephones to TVs to GPS navigating systems as well as all sorts of medical equipment -- in short, modern life as we know it.”
↑↑↑↑↑↑↑↑↑↑↑↑↑↑
Better than sliced bread ... and there ain't much that beats sliced bread.
In the old FT 225 RD ( 2 meter all mode) i used them to replace the 1 diode AM rectifier by a 2 diode rectifier for Am.
Worked like a charm.
In the FT 847 i replaced the bandswitch diode ( universal switching diodes a la 4148 type, with the Schottky ones.
Less noise, lower distortion.
Need some? ;)
Quote:
Originally Posted by kd8dey