[ARC5] HF Converter - the mixer.

[Kenneth G. Gordon]

I find it somewhat odd that so few people consider the so-called "Pullen Mixer" for such an 
application.

>From my study of that mixer, it seems to me to be a nearly perfect mixer for this purpose.

I wonder if Dr. Tom would consider commenting on this?

Here are some links to it which I have published on my website for a number of years.

http://www.w7ekb.com/glowbugs/rx/receivers.htm

...at 9) about half-way down the page...

and

http://www.w7ekb.com/glowbugs/rx/Pullen/PullenMixer.pdf

http://www.w7ekb.com/glowbugs/rx/Pullen/75A4Pullen.pdf

One thing that is not clear from any of the above is that to properly implement this mixer will 
require 4 triodes, not 3, 1 of which would have to be a cathode-follower between the 
triode-HFO and the mixer-proper.

I had planned to use two 7963 submini dual triodes in my implementation of this circuit.

These could be mounted on an octal tube base, with other components, and simply plugged 
into, say, an "ARC-5" receiver in place of the 12K8 for instance. Other parameters would 
have to be "tweaked", of course.

It also appears that the higher the transconductance of the triodes involved, the better this 
mixer circuit works.

Ken W7EKB