Hello, Alot has been mentioned re: the 25V tubes. Currently restoring a RCA CTC24, & came across a CTC39. Question is: Did any solid state sets also use this delta tube? Can both chassis be interchanged between the two for testing? Yoke/Conv.? My guess is yes. What is the 25V all about. Same or much different?

Thank you!

PS the original 25VABP22 is tired on blue & red. Have not rejuvenated. Suitable replacement suggestions? Have not checked the substitution manual yet.

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I have seen delta's in TVs as new as 1983. Don't know what tube it had though.

zenith and even admiral had a 23v crt in the late 70s.all delta gun crts are elctronically compatible.they will show a picture with any chassis.since these are rca crts,have you tried a light tap from a rejuvenator?we had overwhelming success with the rca crts.seems like they responded better than the others.good luck!

I've also had good luck with rejuvenating the older RCA delta gun CRT's, as long as your rejuvenator is no an ancient "atomic blast" model.

In the early days of rectangular color CRT's, the tubes were numbered like 25XP22, 25AP22, etc. These are technically 25" CRT's; but, once installed in the set, there will only be a 23" viewable picture. Despite the fact that the picture was only 23" viewable, many of these sets were advertised as being 25".

After a few years, the FTC cracked down and said the advertised screen size had to equal to the actual viewable picture size. So, if a set only had a 23" viewable picture; then, it had to be advertised as a 23" set.

Sometime around 1970-'71, TV's with 25" viewable pictures came out.

Later, CRT numbering changed to having a "V" in the type number, such as 23VxxP22 (23" viewable picture), 25VxxP22 (25" viewable picture), 19VxxP22 (19" viewable picture).

As far as tube substitution, a later 23V series delta gun CRT will sub for the older tubes like 25AP22, 25XP22, etc. However, a 25V series tube will NOT substitute for an older 25A, 25X, or similar CRT.

23v and 25 inch tubes were an issue back in the shop days.23 inch crts came first.then a manufacturer came up with the 25 inch crt which was in reality a 23 inch tube.they measured the tube diagonally and advertised it a being a 25 inch crt.in the set,however,it produces a 23 inch picture when in the set.when one of those 25 inch sets came in the 1st time,we measured it.same as the 23v tubes.25v crts are bigger.the actually measure out of the set 25.8 inches.for a short time,they were advertised as 27 inch crts,for a short time before this campaign was halted.it was all a gimmick."i offer the largest screen available,we have the largest picture tube in history,etc".all advertising.of course,the greatest advertisment in television history is,"the quality goes in before the name goes on".

Some time past 1990, Sony (and probably others) figured out that the "truth in picture size" law did not apply to computer or professional monitors, and their 13s became "14s", 16 was now 17, and 27 became 29.

I've also had good luck with rejuvenating the older RCA delta gun CRT's, as long as your rejuvenator is no an ancient "atomic blast" model.

In the early days of rectangular color CRT's, the tubes were numbered like 25XP22, 25AP22, etc. These are technically 25" CRT's; but, once installed in the set, there will only be a 23" viewable picture. Despite the fact that the picture was only 23" viewable, many of these sets were advertised as being 25".

After a few years, the FTC cracked down and said the advertised screen size had to equal to the actual viewable picture size. So, if a set only had a 23" viewable picture; then, it had to be advertised as a 23" set.

Sometime around 1970-'71, TV's with 25" viewable pictures came out.

Later, CRT numbering changed to having a "V" in the type number, such as 23VxxP22 (23" viewable picture), 25VxxP22 (25" viewable picture), 19VxxP22 (19" viewable picture).

As far as tube substitution, a later 23V series delta gun CRT will sub for the older tubes like 25AP22, 25XP22, etc. However, a 25V series tube will NOT substitute for an older 25A, 25X, or similar CRT.

Thanks for that explanation. I've always wondered how the "V" designation came to be.