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Old September 2nd 06, 04:52 AM posted to rec.radio.amateur.homebrew
Klop Klop is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 1
Default MRX-40 modification

Reposted.
wrote in message
ups.com...
Hello OM,
I have build the MRX-40 form a kit many years ago. It
work fine but ...
Now I would like to make a small modification to this receiver.
I would like to replace the tuning capacitor with some kind of diode.
I manage to add a small potentiometer with the shaft getting outside
and I remove the initial capacitor. Now I wonder how and what kind of
diode I could use. I dont have also any idea about what to expect in
the
range of tuning.
May be someone else had the same idea

Any help is will be greatly appraciate.
Happy day
72 de Jean (VE2GHI)

Try VU2UPX's excellent circuit:
http://www.qsl.net/vu2upx/Projects/dc_rx.htm
This uses varicaps for tuning in a NE602 based receiver (although this is
for 20m).

Also
http://www.hanssummers.com/radio/varicap/index.htm
for G0UPL's testing of several common diodes as varicaps.
Red LED's came out top!
Does anyone else have info on using them as varicaps for tuning?

73s
Klop