Another RCA CT-100 discovery B8001599

[Electronic M]

Originally Posted by ARC Tech-109

I've been around the back of color TV's for the better part of 40 years and had never seen the CTC-100, was this a unique CRT? I'm not seeing the customary convergence or triad gun layout so I'm somewhat puzzled on this one.

The 15GP22, Its advanced phosphor deposition CBS equivalent the 15HP22, and the much rarer 19" version (19VP22?)...All used electrostatic dynamic convergence (something like 6KV DC with 3KV AC riding on it) instead of the electromagnetic dynamic convergence the 21AXP22 and all later color tubes used until inline gun tubes eliminated dynamic convergence.

There's 3 adjustment screw magnets on purity coil* that are used for static convergence the same as later tubes.

*Instead of degaussing these tubes use a field neutralizing coil on the face and a purity coil on the neck....As a working CT-100 owner it took a little bit wrapping my head around how the adjustments work (and they're still not perfect thanks to a bent shadow mask), but it wasn't hard making them pretty good. There's less to a 15G convergence procedure than most later sets...only problem is HV tends to bloom and fluctuate (especially given I don't have enough high VA voltage regulating line isolation transformers to run my CT-100 off of)and the user pots for focus and occasionally convergence DC have to be tweaked to keep things looking good.
If I had enough room to put my CT-100 and 21CT55 in the same room I could make them share the transformer that feeds the 21CT55.