[Username1]

If the tuner knob causes the picture to go in & out, then you need to focus on getting
good solid connections on each channel. Take the tuner apart, cover off, & use a wood
stick to poke around till you find the most sensitive parts and try and figure out
what is not making good contact. Don't worry so much about voltage checks
or replacing parts. Go after making the tuner solid when on a channel.

In our shop we use to clean all contacts with a gritty cleaner on Q tips,
probably not available any more, today I think the closest thing would
be the mildest valve grinding compound. You could use silver polish
or Ajax, something with really mild abrasive. But we had to remove
all of that stuff after it's use, so whatever you use be sure to use
small amounts, keep it confined, use Q tips, and remove it all.
Then after be sure to spray it with Tuner Cleaner so you
protect it from oxidation......

Be sure the switches are in good shape before moving on to see if it's a
loose component, ground, or tube socket. Clean tube sockets too.....





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