Most things can be fixed BUT if I still had a shop I
would NOT fix a CRT TV unless they understood there
is NO guarantee beyond the front door. Its age
& finding parts not that its a CRT set.
The fact its intermittent may point to an easy fix but
they probably need a hobbyist. What are you doing tonite ??
Drop us the make, exact symptom, model # & or chassis #
and date, maybe its a common easy fix.
73 Zeno