Spectra UHF VCO

[kc7gr]

Hi, gang,

I've got a UHF Spectra in Range 3. It has been programmed for a number of ham freqs, but the VCO is reluctant to lock down around 440 (no surprise).

I was going to try 'painting' over one of the laser cuts on the tank inductor with some conductive goo, but it looks like said inductor has multiple laser cuts in it. It's hard to tell, because there's also black residue on the substrate, most likely from the effects of the laser.

My questions:

(1) Is there a safe way to clean off the black gunk without freaking the VCO out?

(2) When 'painting' over one of the cuts to increase inductance, can I assume I should start with the cut closest to the large capacitor that's feeding the inductor trace?

Thanks in advance.