The Set: Pete Deksnis's Site about the CT-100
Restoring a Vintage Color Television Set
Color Television Chassis
CTC10 is noted for its use of the 'A' version of the 21CYP22, the second-generation 21-in. tricolor CRT that began replacing the 21AXP22 with the introduction of the CTC7. Only used it seems for the CTC10-based 1960 models, the 21CYP22A had phosphor changes that made the picture brighter than its predecessor but with much greater, but hardly noticeable, lag.
An early CTC10-based set looks quite similar to a late CTC9, while a late CTC10-based set looks similar to an early 1961 model with the CTC11 'NewVista' chassis.