Receiver VFO / BFO

A project log for Shortwave Crystal Radio - A blast from my past

Building and tinkering with crystal radios goes back to my childhood of the late 1960's and coming round again.

Dr. CockroachDr. Cockroach 03/05/2020 at 14:510 Comments

Well, you could call the oscillator I am using a BFO or a VFO ( Actually both ). Depends on how you look at it. I have used this circuit and actual build for many years without any problems. Not really state of today's art and it sure is not stable compared to a lot of other circuits out there but it works with just a hand full of parts and never quits.

Here is the circuit followed by the web page link.

I have made a couple of changes to this circuit. First I replaced the upper left 2N3053 with a 22PF NPO cap. I also replaced the lower left 2N3053 with 2 IN914 switching diodes in parallel. I also made this circuit with just a single band in mind so did not need the switch S1a/b