Well, sure, it’s not totally “fixed.” I had tried all the on-line “fixes” for the dots. With the previous PLL board, since VCO5 would not adjust to function, I had totally stripped VCO5, thoroughly cleaned the board, rebuilt VCO5 with new components, reflowed solder for entire board, and it still didn’t help. Yes, at that point I gave up and put in a working PLL board. For the RF board I stripped out VCO1, thoroughly cleaned the board, then rebuilt with new components. Then reflowed solder on entire board. The replacement PLL board got rid of continuous dots. “Repaired” RF board “worked”, but then I had practically no RF output on transmit. I then decided to bite the bullet and replace the RF board too. Now I just have dots on start-up on some bands, but full RF output. Yesterday I made some adjustments on VCO1, which got rid of dots on all bands, for a while. Now I have a problem with VCO1-1, which I think is bad solder. I can adjust T21 to it’s “proper” voltage, and all dots go away, but then, after a while, the voltage there drops and dots come back 22-30MHz.
So, yes, I “cheated” a bit by replacing entire board, and bought myself another set of problems. I am still learning how to repair radios. In the meantime, I am learning quite a bit, and I believe I will eventually save this old 440 from the junk pile. That’s worth a lot to me.
I plan to re-solder all components in VCO1-1 today. If that doesn’t help, I will totally rebuild that section. The other VCO’s in VCO1 adjusted yesterday to function properly, after I removed some residual gunk.
Thanks for your help and suggestions.
73,
Francis WA4ZYN