ITT Mackay 3020A - Fixes
Great receiver and there are only two shortcomings...
First, the Minor Loop Analog board problem.
Usually, this problem manifests itself in an apparent "loss of lock" symptom. You start hearing WWV at something like 9.600 MHz or some such thing. It's pretty disconcerting to find those guys so far off frequency -- you think, "Hey, what are they up to over there in Colorado?" But, then you realize that WWV probably has not gone rogue. And, you start poking around in your premium receiver to see what the heck is going on..
On the "L" revision of the Minor Loop Analog board there is a capacitor and resistor combination that are frequently a problem. If you have an "M" or later version of this board you're in fat city! Problem already solved.
Here's what a Minor Loop Analog board that's gone bad might look like:
The pencil is pointing to R3 -- that's usually the culprit and you can see that the board behind R3 has been getting rather warm.
Next, take a look at C2 right next door. What's this? Some clown has cobbled another C2 in series with the original C2! What the heck is that all about?
Just look at that thing hanging there! What an embarrasment!
BTW, this particular board was still working, in spite of the woefully inadequate "fix". The good news is that you don't need much to fix up a board like this.
And, here is what the board looks like with the new components installed.
Of course, the ultimate solution is to simply upgrade to an "M" level board. It got a bit of a make-over by ITT/Mackay and the problems with C2 and R3 were eliminated. Here's what the Minor Loop Analog "M" level board looks like:
Check out the snazzy new design. The "M" version of the Minor Loop Analog board functions properly without overheating. As Martha Stewart would doubtless say, "It's a good thing"..
Oh, yes, the fan. Or, should I say THE FAN. Sorry, I had to shout over the dang thing. Now, at sea the noise level didn't matter since there was always a cacophony of noise aboard ship. But, here in the shack I definitely replace the fan with a more quiet model. Worth every penny. And, that's all I have to say about that..
The ITT/Mackay 3020A receiver. It's worth keeping the old gal running..