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After recapping the chassis and after the preliminary checks, I applied power for my first time. The chassis is on the bench with deflection yoke, convergence coils and tuner attached but without the CRT.
The set powered up and appeared healthy. The first check is horizontal output performance: I checked the horizontal drive: RCA notes says 180p-p waveform and I measure 150v p-p. I adjusted the horizontal efficiency coild for minimum HO Tube cathode current. The HO Tube initially very slightly started to glow red on the plate after about 5 minutes and after adjusting the efficiency coil for minimum cathode current, the red glow disappeared.
Similar to the other CTC-5 thread, the HO Tube bias is a bit low and I attributed this on my set to the low drive at 150v p-p. I tried swapping the 6CG7 Horizontal Oscillator Tube with the 6CG7 Vertical Oscillator. The other tube reduced the drive to 130v p-p which seems to me that I have a couple of tired old tubes. (All the tubes are original to the set!)
This was one of the best preserved old sets I have ever had a chance to work on (in recent times). I plan to check the full alignment as I will be curious if, under this set's almost ideal 55 year life, how much it will have drifted.
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