Bought a '65 Magnavox console

[AUdubon5425]

Hi everyone,

I'm about to finish re-capping this set (Magnavox U44) but have a question:

I was able to get a picture on the set, but it is very dim - only viewable in a dark room with the brightness almost fully up. When I pot the brightness all the way, the picture goes "negative" - like looking at a photo negative.

Any advice for me? Maybe some circuit in particular to double-check? Unfortunately, I don't have a CRT tester, I have a gut feeling the crt is bad, but am trying to eliminate any other possibilities for this condition.

Also, where could I find information on which tubes are compatible with a 23MP4, in case I have to start searching for one?

Thanks,

Ryan