[Collins] 51J4 vs 75A3?

[Dr. Gerald N. Johnson]

On Thu, 2007-02-15 at 14:58 +0000, ehertz wrote:
> Hello! thanks to everyone for all the responses. I am unlikely to be able to afford an A4 anytime soon, unfortunately. I was wondering if you had an opinion as to whether an A3 with a product detector and agc mod would be any "worse" of a ham receiver than the J4 with the prod detector/agc mod (dallas lankford)? 
> I've been satisfied with the J4 but the bandswitching is killing me. If a modified A3 could perform at least as well as the J4 then it could be a good replacement for the J4 in my operating position.  However, if the opinion is that the J4 is better than the A3, I would likely stick with the J4.
> Thanks again to everyone
> Eugene

I think the circuit arrangements are similar, though the mixers in the
A3 may be noisier than those in the J4. The product detector and AGC
mods are very similar. Other than the bandswitching, the differences are
probably minor.

You might look for a 4" diameter crank knob for the J4 bandswitch, and
then do a good lubrication job on all those pieces as you fix whatever
now ails the bandswitching.
-- 
73, Jerry, K0CQ, Technical Advisor to the CRA
All content copyright Dr. Gerald N. Johnson, electrical engineer