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I wonder if the flyback is completely bad in this case or just has been overloaded but still has a chance...On a CTC-16 and CTC-38 both had power supply or bad solder joint problems which caused no voltage to the horizontal oscillator. This overloaded and destroyed the 6JE6 tubes but repairing the oscillator power supply and replacing the output tube brought back proper operation.
If possible though a new flyback is the best solution along with a cathode fuse and current adjustment...have had a flyback fire in a CTC-31 which completely destroyed the flyback and HV tube socket. Don't know if this was an arcing problem, just bad flyback or output tube overload. The portable sets had either a circuit breaker in the horiz output cathode, a thermal fuse on the HO tube or both but for some reason the consoles/metal table top models never had this protection.
The easiest check for oscillator operation is to measure the negative grid voltage on the horizontal output tube. No voltage or weak voltage indicates poor or no oscillator operation.
Also I have had problems in the 6BK4 circuits cause problems in Magnavox sets where the flyback was overheating.
I have put in a fuse clip in the horizontal output cathode circuit and first put in a 6 volt fuse lamp to set the efficiency coil (minimum brightness on the lamp) then replaced the lamp with a 300 ma fuse.
Last edited by Chad Hauris; 11-28-2007 at 10:34 PM.
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