View Full Version : Picture tubes--rate them...


rca2000
04-19-2014, 11:05 PM
In my own obversations--There seem to be "best and worst" picture tubes out there.


I will rate my own opinions on the various "generations" of color tubes I have seen/heard about.

The first generation. 15GP22/15HP22. NOT too good, they don't hold up well, mainly due to poor seals.

2nd gen--19" color tubes (not sure of the #'s) These do NOT seem to be much better than the 15" tubes, not too many made--do NOT seem to have real long lifespan--but than I have NO personal experience with them and have read only scant info.

3rd gen. 21AXP22/a. These were a LOT better. Metal tube, SOME seal problems--but not NEAR as bad as the 15" tubes. If seals are good--these CAN last a long time. I have seen a number of them test like NEW after all of these years.

4th gen--21CYP22 types. All glass, seem to hold up SOMEWHAT well. NOT as refined as the successors, IMHO.

5th Gen. 21FBP/JP series types. These are all glass and are a LOT brighter than any before them. They can last a LONG time--and do NOT often go to air, unlike those before them. Of course, like any bonded tubes, the JP's and such get bad cataracts often. All in all--the BEST of the roundies===and pretty much the last gen of them too.

1st gen rect. 22EP22 or such, 1957, made ONLY by sylvania or westinghouse. Did NOT work out well at ALL. had a LOT of convergence and purity troubles VERY few made, before pulled off production.


2nd gen rect. NVC 23EGP22. 1964. THIS is a tube that should have NEVER been made--or at least they should have recalled it like the earlier 22" attempt--but they did NOT do so. NOT likely to be good, after all of this time. I personally have NEVER seen a good one. Even in the late 1970'S--they were dying then !!

3rd gen rect..25AP22 GP22 types. Better than the 23EGP22--but still not too good. I have seen a LOT of bad ones--even 30+ years ago. Still, other than cataratcs--a fair chance of finding one good now.

4Th gen rect---Zenith's "chromacolor" tubes. VERY good tubes. MUCH better and brighter than others before. Can last a LONG time, likely to be good even today. ALso in this grupo are RCA'A "hi-lite" tubes with improved RE phospor. Likely good also--but NOT as good as the chromacolor matrix tubes.

5TH gen--Sony's "trinitron" tubes. Some of the earliest ones were not the best, but soon they were improved and often lasted a long time. VERY good picture, rivaled ONLY by chromacolor II tubes. Fair chance of finding a good one today.

(710AB22 type Sony 26" tubes.. These are TERRIBLE tubes !! Little chance of getting a good one today. They were dying OVER 25 YEARS ago !! On a par wit the 23EGP22 tubes for reliability/longevity. BUT--when working--they DID produce a great picture. )


2nd gen Chromacolor tubes--chromacolor II. (DELTA gun types). There are the BEST tubes EVER made IMHO. They go on FOREVER !! I have hardly EVER seen a bad one !! And the picture they produce is about UNBEATABLE !!

RCA late 1970's delta 25" tubes. NOT too good. DO NOT seem to hold up well. Not NEARLY as long as the Zenith tubes of the era.

Zenith "thin neck "tri-potential tubes". NOT real good. DO NOT seem to hold up NEARLY as well as the delta gun tubes. fair chance of finding a good one today. STILL better than the 110 degree tube Zenith made from 1991-99, though...


RCA late 110 degree 1970's to late 1980's in-line tubes with the "plug-in" focus connector. NOT too bad--have seen a LOT of good ones. Seem to hold up pretty well.

RCA 110 degree in-line type tubes late 1980's till 2000's. (Most other brands of that period too). (NOT "mini-necks). Good tubes, often made by Hitachi. VERY good tubes, last a LONG time, only seen a few bad ones. Usually a "bonded " tube with sealed -on yoke. High likelihood of finding one good today.

"Mini-neck" tubes. All brands. Often used on 20" and smaller sets. DO NOT hold up too well. Do NOT like to be rejuvinated either. Of course a small set is more likely to have a good tube, particularly a 13" or smaller set, since they often were used less often.

And...the Zenith "experiment" from about 1991, when LG took over. Supposdely was to produce a "low-cost, cheap to build, high-quality tube". What they GOT--was a WORSE tube than even a 23EGP22 or 710AB22 tube !! These were dying in WARRANTY, left and right, within a couple of YEARS from new !! Worse yet--they do not normally just "go dim" like a normal tube--they like to KILL the board in the SET !! VERY low likelihood of finding a good one today.


Share your own thoughts...

miniman82
04-20-2014, 09:36 AM
If your only criteria is how long they last sure, but being a picture tube I'm sure picture quality and color rendition fit in there SOMEWHERE...

15GP22 FTW.

Tom S
04-20-2014, 11:19 AM
I worked for a store here in Stevens Point & Wausau Wisconsin, I replaced more Zenith CRT's with short problems in the 25" sets. Then when it would short it take the main module out too. A shame a company so great turned to trash then disappeared from the face of the earth. Thanks Goldstar and LG. Too bad the USA can't build electronics that are affordable to the general public with some quality behind it. Yeah right made in the USA for big bucks. Well I've vented enough.

Electronic M
04-20-2014, 12:54 PM
The 15G was on par with the 21AXP and metal cone monochrome CRTs of the 50's as far as reliability goes. Why the 21AXP is harder to find than the monochrome tubes and the 15G harder to find than the 21AXP ultimately comes down to how many of each were made.

Also I have seen one (and heard of some other) 21FJP tube going to air without being necked so those tubes are not completely leak proof either.

You over look the fact that the Japanese beat our 23EGP to market with their own tube (the number escapes me at the moment).

Performance wise it is dependent on phosphor color rendition (the round tubes especially the earliest ones have it hands down in my opinion) and the electronics driving the tube. Most roundy tubes I've seen run tend to have soft focus, but on a CTC-4 (with a 21FJP retrofitted in) and a Zenith roundy I got last year the focus and video circuits drive the tube to have a monochrome picture with detail sharp enough to rival my Zenith Chromacolor.

dieseljeep
04-20-2014, 01:29 PM
The 15G was on par with the 21AXP and metal cone monochrome CRTs of the 50's as far as reliability goes. Why the 21AXP is harder to find than the monochrome tubes and the 15G harder to find than the 21AXP ultimately comes down to how many of each were made.

Also I have seen one (and heard of some other) 21FJP tube going to air without being necked so those tubes are not completely leak proof either.

You over look the fact that the Japanese beat our 23EGP to market with their own tube (the number escapes me at the moment).

Performance wise it is dependent on phosphor color rendition (the round tubes especially the earliest ones have it hands down in my opinion) and the electronics driving the tube. Most roundy tubes I've seen run tend to have soft focus, but on a CTC-4 (with a 21FJP retrofitted in) and a Zenith roundy I got last year the focus and video circuits drive the tube to have a monochrome picture with detail sharp enough to rival my Zenith Chromacolor.
Tom! You're thinking about the 15" CRT, with the roundie neck. Toshiba built the set and CRT.
Motorola started building the TS908 with the 23EG in late 1963. In fact, the first models didn't have UHF, as required after May 1964.
IIRC, the Sears rectangular 15" was considered to be a 1965 model. RCA came out with their CTC17, using a 25AP22 in spring of 1965. It had a CTC16E knobs and control panel.

rca2000
04-20-2014, 01:58 PM
If your only criteria is how long they last sure, but being a picture tube I'm sure picture quality and color rendition fit in there SOMEWHERE...

15GP22 FTW.

Well--since most of these sets we seek are now OVER 40 years old and older--life span does INDEED matter to us. Pix quality does matter, but if the tube is dead it does NOT matter then.

And addendum to the Sony 710AB22... They will NOT take rejuv. at ALL. I tried on a number of them some years ago. At FIRST--they would APPEAR to come up...but THEN fade down, often before my EYES !! This actually applies to nearly ALL trinitron tubes--when they die...BURY THEM.

David Roper
04-20-2014, 02:55 PM
Sylvania did NOT make or market ANY color sets with RECTangular color tubes in the 1950s. The contours of THE mask merely make it appear to be a rectangular tube...kind OF.

http://earlytelevision.org/images/sylvania_31C606-2.jpg

I agree with Nick that to concentrate on the tubes' durability and largely ignore/dismiss the very factors that most affect image quality (increased brightness of later rare-earth tubes sacrificed some hue range) misses the POINT.

rca2000
04-20-2014, 03:18 PM
SOMEONE made an "attempt' at a 22" color tube, in 1957. A couple of members have sets with them. I THINK they have a "big neck" like a roundie. It was either sylvania or westinghouse, I think.

miniman82
04-20-2014, 04:15 PM
Sylvania did NOT make or market ANY color sets with RECTangular color tubes in the 1950s. The contours of THE mask merely make it appear to be a rectangular tube...kind OF.

http://earlytelevision.org/images/sylvania_31C606-2.jpg

He said Sylvania or Westinghouse, which means he was probably thinking of this set not the Saratoga:

http://earlytelevision.org/westinghouse_h22t155.html

http://earlytelevision.org/images/westinghouse_h22t155.jpg


Sylvania did however make 21AXP22's, my Saratoga has the original Sylvania branded CRT in it with great emissions.


http://miniman82.4t.com/images/Sylvania/sylvania7.JPG
http://miniman82.4t.com/images/Sylvania/sylvania9.JPG

marty59
04-20-2014, 04:26 PM
No mention or love for the 21CYP22?

davet753
04-20-2014, 05:30 PM
IMHO, Zenith deserves the award for best tube, and the worst. You can't hardly kill the delta gun tubes Zenith produced.

Then, in the early 90's, Zenith started producing tubes that would hardly make it past the warranty period. I remember replacing these tubes (especially 25" and 27") under warranty, and having them come back a year or so afterwards (after the warranty expired) with bad tubes again. Whether a rebuilt tube from the factory or aftermarket, these tubes just wouldn't hold up.

I also remember working on a lot of the old Motorola "Works in the Drawer" consoles and never did note a bad picture tube in those sets.

rca2000
04-20-2014, 07:04 PM
I mentioned the 21CYP22. It is considered the 4th gen. or so of roundies. I have one in a CTC-7 that am pretty sure is great. They seem to hold up fairly well, maybe not as well as the FB types--but then--they made a LOT fewer of them too. Fair chance of finding one good today.

rca2000
04-20-2014, 07:09 PM
He said Sylvania or Westinghouse, which means he was probably thinking of this set not the Saratoga:

http://earlytelevision.org/westinghouse_h22t155.html

http://earlytelevision.org/images/westinghouse_h22t155.jpg


Sylvania did however make 21AXP22's, my Saratoga has the original Sylvania branded CRT in it with great emissions.


http://miniman82.4t.com/images/Sylvania/sylvania7.JPG
http://miniman82.4t.com/images/Sylvania/sylvania9.JPG

The top set Is the one I was referring to--with the 22" tube---that did NOT take off. NOT a well-made set--hot chassis and such and VERY few are around evidently.

Tom S
04-21-2014, 08:09 AM
Tom! You're thinking about the 15" CRT, with the roundie neck. Toshiba built the set and CRT.
Motorola started building the TS908 with the 23EG in late 1963. In fact, the first models didn't have UHF, as required after May 1964.
IIRC, the Sears rectangular 15" was considered to be a 1965 model. RCA came out with their CTC17, using a 25AP22 in spring of 1965. It had a CTC16E knobs and control panel.

No I'm talking about the mid 90's sets of Zenith

dieseljeep
04-21-2014, 08:46 AM
No I'm talking about the mid 90's sets of Zenith

No Tom S. I was referring to Tom Carlson's post, regarding the big neck Toshiba.

dieseljeep
04-21-2014, 08:57 AM
SOMEONE made an "attempt' at a 22" color tube, in 1957. A couple of members have sets with them. I THINK they have a "big neck" like a roundie. It was either sylvania or westinghouse, I think.

I understood, that it was CBS-Hytron that built that CRT. They also built the 19" tubes for CBS Columbia, Motorola and Raytheon.
They were one of the patent holders for the tri-color phosphor dot design. :yes:

DavGoodlin
04-21-2014, 11:43 AM
I understood, that it was CBS-Hytron that built that CRT. They also built the 19" tubes for CBS Columbia, Motorola and Raytheon.
They were one of the patent holders for the tri-color phosphor dot design. :yes:

Was it a 19VP22 that Motorola used in its 1957 color set? That was also a troublemaker. I think there was a kit to convert the set to a 21AXP22.

David Roper
04-21-2014, 12:16 PM
The 19VP22 was only used in 1954-55 sets. By 1957 those sets were already getting the 21AX conversions.

Wherever the 22" rectangular color tube came from, only Westinghouse ever offered it in a production set.

andy
04-22-2014, 12:20 AM
...

DavGoodlin
04-22-2014, 05:57 AM
I've never been a fan of the low focus voltage CRTs that were popular in many of the early color portables. A really strong tube looks decent (still not as good as a normal CRT), but they lose focus very early in life. Sets using them usually don't even have a focus control. There were usually 3 voltage taps that you could plug a jumper into. The settings were blurry, less blurry, and more blurry. Fortunately, they stopped making them by the mid 70's. Even the late model Portacolors switched to a high focus voltage CRT with a voltage divider connected to the anode.

Yes! I almost forgot how difficult it was to get good sharp focus on the 11WP22 used in GE sorta-color and 15LP22 used in the RCA CTC22.

dieseljeep
04-22-2014, 09:06 AM
I've never been a fan of the low focus voltage CRTs that were popular in many of the early color portables. A really strong tube looks decent (still not as good as a normal CRT), but they lose focus very early in life. Sets using them usually don't even have a focus control. There were usually 3 voltage taps that you could plug a jumper into. The settings were blurry, less blurry, and more blurry. Fortunately, they stopped making them by the mid 70's. Even the late model Portacolors switched to a high focus voltage CRT with a voltage divider connected to the anode.

I like the way you described the focus settings.
I owned an early model CTC22, that was only a few months old, when I got it and was amazed, with the picture. It was razor sharp!
I never was impressed with the picture on the CTC36, or the CTC53.
As said before, When the CRT's aged, it was harder to get sharper focus. :no:

Tom S
04-22-2014, 08:44 PM
No Tom S. I was referring to Tom Carlson's post, regarding the big neck Toshiba.

Oh Ok Sorry, understand.

Alastair E
04-23-2014, 01:25 PM
Yes! I almost forgot how difficult it was to get good sharp focus on the 11WP22 used in GE sorta-color and 15LP22 used in the RCA CTC22.

Ah--Reading That takes me back a bit! Years ago I had an American built for the UK market a set called a 'Teleton' It was a 12 or 14" set with a delta type CRT and full of valves although it was actually a hybrid set, with a modified NTSC to sorta simple PAL decoder--Had horrible colour rendering too
(I think these sets gave the UK based TV Trade joke--Never Twice Same Colour--NTSC....!)

--I have no idea who actually made the set, but that had one of those horrible unipotential CRT's that were popular in the 70's no focus-control-The CRT was tired and dark with terrible focus when I had it, even re-juvenating didnt help much....

There were a few UK made and Japanese sets that used them too, Horrible focus on 'em.

I did actually modify an Hitachi set that used a unipot CRT and fitted a Mullard A56-120X, a 22" Delta gun high-focus tube and IMO probably the best European CRT ever made. The picture difference was astounding!
--I took a HV diode from input to tripler and used a Grundig 'Metrosyl' focus-control, Worked brilliantly.

Sure there's an American equivalent to the A56-120X with a number like 560HWB22,--or summit but forget the actual number--I do remember the '560' and the '22' but forget the important type letters....

Electronic M
04-23-2014, 02:58 PM
The first numbers on US CRTs are screen size in inches so there would be no American tubes ###XXP22 unless that failed 'convert to metric' movement managed to hit our electronics industry.

dieseljeep
04-23-2014, 06:48 PM
Ah--Reading That takes me back a bit! Years ago I had an American built for the UK market a set called a 'Teleton' It was a 12 or 14" set with a delta type CRT and full of valves although it was actually a hybrid set, with a modified NTSC to sorta simple PAL decoder--Had horrible colour rendering too
(I think these sets gave the UK based TV Trade joke--Never Twice Same Colour--NTSC....!)

--I have no idea who actually made the set, but that had one of those horrible unipotential CRT's that were popular in the 70's no focus-control-The CRT was tired and dark with terrible focus when I had it, even re-juvenating didnt help much....

There were a few UK made and Japanese sets that used them too, Horrible focus on 'em.

I did actually modify an Hitachi set that used a unipot CRT and fitted a Mullard A56-120X, a 22" Delta gun high-focus tube and IMO probably the best European CRT ever made. The picture difference was astounding!
--I took a HV diode from input to tripler and used a Grundig 'Metrosyl' focus-control, Worked brilliantly.

Sure there's an American equivalent to the A56-120X with a number like 560HWB22,--or summit but forget the actual number--I do remember the '560' and the '22' but forget the important type letters....
I would like to see a picture of the U.S. built set with the pseudo PAL decoder.
Maybe it was a Japanese firm, that wanted a place in the European, British market. Japan uses a form of NTSC.
The Kuba Porta-color that everyone refers to, has no resemblance to the U.S. model, outside of the cabinet, CRT, yoke, convergence assembly and flyback transformer.
BTW, that's what makes this hobby interesting. :thmbsp:

Alastair E
04-24-2014, 03:31 AM
I would like to see a picture of the U.S. built set with the pseudo PAL decoder.
Maybe it was a Japanese firm, that wanted a place in the European, British market. Japan uses a form of NTSC.
The Kuba Porta-color that everyone refers to, has no resemblance to the U.S. model, outside of the cabinet, CRT, yoke, convergence assembly and flyback transformer.
BTW, that's what makes this hobby interesting. :thmbsp:


Sadly, My Teleton is long gone, but here is a thread on a UK forum of the same model set, there's a PDF link that explains the weird decoder they had....

http://www.vintage-radio.net/forum/showthread.php?p=72223

Maybe I'm wrong about it being a USA made set--Possibly it was some Japanese or maybe even Chinese origin set!

--It just sorta Looked USA made to me at the time years ago, Steel cabinet etc,--, Has all USA designation valves, like 17JZ8, 3AT2 etc....

dieseljeep
04-24-2014, 12:54 PM
Sadly, My Teleton is long gone, but here is a thread on a UK forum of the same model set, there's a PDF link that explains the weird decoder they had....

http://www.vintage-radio.net/forum/showthread.php?p=72223

Maybe I'm wrong about it being a USA made set--Possibly it was some Japanese or maybe even Chinese origin set!

--It just sorta Looked USA made to me at the time years ago, Steel cabinet etc,--, Has all USA designation valves, like 17JZ8, 3AT2 etc....

Many thanks for the information!
I was hoping that you could source this information.
The set was made by General of Japan, as stated in the theory text. They were never a big player in the U.S. market, although, I did work on a few of their products. The small screen B/W Philco, that Ford sold with the Mustang logo, was General sourced. Everyone here knows what that set is worth.
Regarding the valves, Panasonic was the only Japanese concern that used, what we would consider to be Euro-valves in their products. Motorola seemed to run a close second. :yes: