Hi, I'm recently into refurbing some old
vintage radios, I'm talking here of just
getting them going to as close as original
spec with minimal changing of componants
I've done three so far a Hallicrafters S-77
an R1155 and in the process of a Collins
TCS12, they all seem to follow the same
condition, ie from switch on after changing
obvious faults shorts on caps supply
electrolytics etc there is much crackling
musty smell poor spec etc then over the
next few hours they make a remarkable
recovery! spec comes back and the crackles
and pops subside to an almost acceptable
level, but here's the rub they never really
subside completely, you are left with this
background crackle and if you leave the set
off for a few days it gets worse again, its
nothing specific as I've tried to trace it
it seems to come from all over IF AF front
end etc, I'm not talking backgound hiss, its
a crackle, sometimes quite bad other times
almost completely gone? is this a general
breakdown of componant material? ie carbon
in the resisters or similar? has anyone else
out there found this problem if so whats the
answer?
from Ron.