A screen shot would be nice but... just because a tube checks good
it dont mean its good. The worms make me think an IF tube.
AGC usually messes up the sound if overloading or washes out
(no contrast) the pix.
Anyhows always start with cleaning & adjusting then tubes next.
Its the cheap & easy way to go. Two of the IF tubes & several of the
other low level tubes are the same. Try swapping them & see if
you get different symptoms.
Dont forget the lost art of tapping. Light tapping of tubes often
show a bad tube or dirty socket. Give light taps one tube at a time
while watching the pix in a mirror.
nuf fer now
73 Zeno
