I did scrape it until I saw grey colored fiberglass with pieces falling out. I do not plan to heat up the area where I filled in traces though your advice is great. Next time I do repair like this I will use JB Weld or other alternatives. I just used what I had at home. I usually use stranded wires to fix burned traces, though no issues with traces on this amp. They remained intact.
I am still puzzled how contamination can conduct so well. I do need to beef up +45V trace in one spot though. Copper tape could work quite well in that area but I never tried it in the past.
The electrolyte in the capacitor is conductive. It can start the conduction and after the board heats up and become carbonized, the process continues as long as there is voltage present.
Copper foil tape and copper eyelets to replace vias may have their uses in very expensive or specialized circuits but for car audio, wire works well enough. In the rare situation where skin effect becomes an issue, litz wire would be a better option than normal wire but skin effect rarely comes into play in board repairs.
Copper foil tape and copper eyelets to replace vias may have their uses in very expensive or specialized circuits but for car audio, wire works well enough. In the rare situation where skin effect becomes an issue, litz wire would be a better option than normal wire but skin effect rarely comes into play in board repairs.