[julianburke]

That Colorama 22JP22 is a obvious replacement in your set. 22J's were not that great of a tube as I replaced many of them. They looked great when healthy but did not have the life of a 25X. CRT cataracts are NOT peculiar to only Zenith tubes but to all bonded face CRT's where the mixtures of the Corning, DOW or GE resin was mixed inappropriately. The resin also absorbs water or humidity which helps this process along such as stored in a damp basement or garage. The mixtures of resin were not a big deal in the day as it didn't seem to make a difference and looked good but only time proved this one out. At time of installing the bonded face, you mixed a curing agent to make it set up as it DOES NOT come premixed for obvious reasons and many people either put too much or too little curing compound in the mixture. However, mostly age, humidity and sunlight are responsible for the "cataract".

When replacing tubes, you went for price and Zenith CRT's from Graybar (or other distributor) were more expensive than RCA or others.

However, Yes, Zenith did use RCA tubes on many occasions. We were a Zenith dealer and repair shop and saw several RCA tubes with a Zenith label pasted right over top the RCA label. They didn't bother to take the RCA label off. Boy this sure made Dan Geddings mad as he was a Zenith die hard! One time he opened a 12BH7 tube from a Zenith box and the tube was branded "Admiral" with red label. Dan took it back to Graybar for replacement and he was really mad because he hated other brands esp Admiral. It was and still is common practice for all manufacturers to trade around as it is very expensive to set up tooling for a specific tube or light bulb. I wonder how many of those tubes got "misboxed"? As often stated, "A rose by any other name still smells just as sweet"!! In being curious, I wonder if anyone up the line boxed the "Admiral" labeled tubes thinking "what difference does it make"? It's the same tube! And rebranding it would be more costly, unpractical if not impossible at that plant.

At one time the manufacturer who could make or source CRT's would stay for market share of sets sold and sales would sometimes exceed production limits. This is probably what hurt Curtis Mathis as they were 100% dependent on outsourcing. Their later years used Samsung for 13" color & B&W, Sharp for 19" and Magnavox for big screens.

In updating this post, I have seen about 4 Zenith TV's with original CRT's that were rebranded "Zenith" over on top of the RCA label. Yes, we scratched our heads at that time on that one. Likely it was a lazy employee on a Friday afternoon. One person I could've asked is Jack Van Hutton who was a field engineer at Zenith but he passed away years ago but I will see what I can do to find someone else who might know about this.