The Set: Pete Deksnis's Site about the CT-100
Restoring a Vintage Color Television Set
Return to ETF
1 May 2008
Still have time?
Skim or peruse this catch-all page
devoted to anything related to vintage color TV.
Color Television Chassis
CTC is the RCA
designation for its
color television chassis
is a reference that lasted throughout the domain of analog television. CTC numbers 1 through 16 are indeed considered vintage. Click a CTC number and read tidbits from the first decade of RCA Color Television.
RCA Lancaster, still churning out the 15GP22 in August 1954.
RCA TK-41C COLOR CAMERA OPTIC PATH
Sounds like a plan to me...
Back in 1955 when NBC converted its live program capability to color, there must have been a master plan.
Here you see the 1955 east and west coast facilities from the standpoint of the 'video man.'
Over here in New York you see a nearly eye-level 21-in. model 21-CT-55 flanked by two raised CT-100's.
On the right, the Burbank control room had a triptych also, but all three were 21-CT-55's.
Thanks to Steve Dichter for the photos.
1953 NTSC red
is very inefficient. Red phosphor is blasted with at least twice the energy of the other primary colors in the 15GP22.
It is, therefore, common for the red gun in a 15GP22 to be weak compared to its blue and green partners. The procedure for getting good color balance cuts back on the blue and green during setup and leaves some headroom, so that, although the resulting video image will be less bright, it will nonetheless reproduce a picture with minimal electrical and phosphorescent distortion.
Here is an over-the-air example of red from an eyeball-balanced CT-100 with a good red gun. Plans are forming to calibrate the set using instruments in early 2007 that will ensure, among other parameters, a correct Illuminate C white.
We all know by this time that the venerable CRT is taking its last gasps (of vacuum?). Sure CRT sets will still be around for a while. Remember Radio Shack selling 'Lifetime' receiving tubes for years after RCA and other major makers shut down tube manufacturing.
I've said it before. If I had to replace one of my CRT wide-screen HD sets (one direct view and a projection), it would be with a carefully selected DLP.
Now, interestingly, Consumer Reports has published a list of HD television recommendations, and not one CRT (or Plasma) made the creme-de-la-creme top of the heap. Not one plasma? Good!
What did make the 'Excellent' list were five LCD's and seven DLP's.
Let's hope that Scotty will be selling 'Rebuilt' cathode ray tubes for years.
1953 NTSC red
When the FCC released its annual report for 1953, the 22-page document dealt heavily with the newly approved compatible color television. In that report it was noted that the cost of a 15GP22 to a television manufacturer would be between 175 and 200 dollars (the cost of a budget black and white set). This 1953 RCA graphic indicates how inefficient the 15GP22 red phosphor actually is and why the other primaries are electrically subdued by a correctly adjusted CTC2 matrix.
Relative sensitivity to excitation of each 1953 NTSC primary color.
15GP22's represented a milestone in the development of tricolor picture tubes.
First such tube in 1950 had blue phosphor that glowed too long after excitation was removed.
Red phosphor in 1950 had to be augmented with a red filter, which greatly reduced the light output of the tube.
Tricolor History Spotlight
By mid-1953, RCA sold CRT manufacturers technique, material, manufacturing hardware, and the usual cost of a license to build the 15-in. tricolor CRT.
It worked. General Electric was one of the few manufacturers to make, under license from RCA, the 15GP22. Sylvania was another.
But by the start of 1954, CBS had blunted further development of 15GP22-like tricolor cathode ray tubes by RCA.
CBS had in production a version of the 15GP22, the easier-to-manufacture 15HP22. This tube was the first to deposit the three primary-color phosphors directly to the inside of the faceplate, the way itís done today.
An ad from the second month of 1954 touting the superior design of the CBS 15HP22.
That left RCA holding the proverbial bag, in which a 19-in.15GP22 clone, officially known as the C-73629, resided.
Authentic picture of the developmental
RCA 19-inch tricolor kinescope
It is known that GE and other manufacturers, Westinghouse for another, dabbled with the RCA C-73629 design. While RCA never produced a 19-in. tricolor CRT, it is quite possible that GE did, because GE listed a 19TP22 in its 1962 CRT catalog.
The GE 19TP22 differs from a 15GP22 in only two areas: physical size and deflection angle. The 19TP22 has a larger funnel to accommodate the larger phosphor dot plate (yes, it was still flat) and the deflection angle increased to 60 degrees from 45 in the 15GP22. The latter allowed the overall length of a 19TP22 to be two inches shorter than a 15GP22.
Today we know that the rapidly developed 21-in. RCA 21AXP22 swamped all the 15- and 19-inch tricolor CRTs around. Today only three of CBSís brilliant 15HP22ís and about 140 of RCAís genesis 15GP22ís are known to have survived. Examples of the RCA C-73629 and GE 19TP22 have not been foundÖ so far.
December 16, 2006. I was watching a colorful Parrot program on PBS and grabbed my camera when a group of Macaws showed off the 1953-color hardware beautifully. Not particularly good pictures were taken from the CT-100 screen, but interesting color nevertheless. Click
No one is more ready to sing the praises of high definition ATSC television than I, but there's a problem in paradise. I see it all the time here in the Big Apple coverage area, the birthplace of network television. Based on my five years of receiving and viewing ATSC-based over-the-air television, when NTSC is bad, you can still watch a snowy, noisy picture. When ATSC is bad, its nerve-wracking!
CT-100 screen shots of the 2007 Rose Bowl parade.
A look back at
CT-100 screen shots of the 2006 Rose Bowl rainstorm.
There are five known 1954 CBS RX-90 color television sets.
One sold on eBay in January 2007.
Here is its story.
Obituaries touting the death of NTSC television may be premature...
Here's a quote from a February 7, 2007 article on the TVPredictions.com web page speculating how the two-year-away switch to all digital over-the-air TV may be premature.
"The Digital TV transition will take place in just two years. And a recent survey by the Association of Public Television Stations says most Americans are still blissfully unaware it will happen. More scary is that viewers who get their TV signals from off-air antennas don't have any idea what's going on. (Cable and satellite viewers will likely be able to get converter boxes from their TV providers.)
If the government doesn't get serious -- and soon -- one of two things will happen:
1. Fearful that their constituents will storm the gates when they suddenly can't watch TV on February 17, 2009, Congress will be forced to extend the deadline another year or two.
2. The deadline will stay in place -- and millions of consumers will lose their TV signals.
The first option would be messy. The second one could be nasty."
Although I for one don't agree that the first option is 'messy.'
If I ever
felt the need to
-retire, Iíd set myself up in a
Consulting Editor for Technical Content
One could even start a
to train talking heads how to pronounce butchered technical terms, e.g., Data and Electricity (itís data as in Dayton and for Godís sake fools, thereís no Z in electricity).
Check the Hoffman website as of 8:45 a.m. February 19, 2007. Youíll see a sliding timeline that says, ď1955 First Color TV on West Coast.Ē
Hereís the picture. Itís clearly the 1954 15-in. RCA CT-100.
Hereís a Hoffman advertisement. Itís clearly the 1954 15-in. Hoffman color set.
Now here next is a 1955 Hoffman color set. Iím sure this is the one they meant. But it was hardly the ďFirst Color TV on West CoastĒ as demonstrated by a goodly number of CT-100ís in homes in 1954.
[Old editors simply CANNOT not edit.
But these are very close to what came off the modem.]
From: Royden G. Anderson Subject: CTC12 TVs
Date: Mon, 26 Mar 2007 03:16:12 +0000
I have been servicing TV for over 50 years, opened my own business in 1954. Serviced RCA color from CTC9 era. Mention of CTC12 on your site instantly brought into my mind the first horizontal chassis from RCA's Bloomington plant.
I visited that plant in late 1962 and saw the transition from CTC11 to CTC12 at that time! About a dozen assembly lines were running and some 11s were coming off of a few. I had no knowledge of the 12s being made before that visit and it was the start of full scale production for competing brands. Admiral's were getting labels put on chassis and being stacked for cabinets that were coming in during the next week. I loved the 21FBP22 round tubes, great flesh tone and fun to set up sets with that tube. The yokes were keeping copper mines in business, RCA winding their own yokes, telltale 274 source code on them.
I bought the RCA test jig which came with a FREE color bar-dot-crosshatch generator. The kine was a factory reject, only in the respect of having a half dozen phosphor dots missing in various spots. Not good for new set production but worked fine for a jig!
The 12s were compatible on the same jigs as the 11s. I added to my jigs as the RCA chassis evolved, made my own for the 25" tube type rectangulars, did the same for the CTC40 and CTC44's with solid state chassis. I still have dozens of RCA yoke and convergence adaptors that allowed servicing "off brands" on my RCA jigs.
I just tossed out the jigs in 2003, with reluctance, but I needed room for more SAMS filing cabinets. Jigs were not generating ANY revenue anymore. As a matter the SAMS are not either!
I have several semi-jigs for CTC175 and upwards to allow pulling chassis for testing on discarded table-model sets. With cheap replacement TVs now, not much chassis pulling.
I'm 71 now and keep business open as a hobby. I own ANDY'S TV SERVICE in Palmer, Michigan near Lake Superior.
I was fortunate to get into TV when I did, had a lifetime of fun in the process!
Royden G. Anderson
Here's an amusing little quip from my
Consulting Editor for Technical Content
Any Voice of Music fans out there? I certainly was. As a teenager I'd save my after-school-job earnings and birthday money for a major electronics buy -- a Gonset Communicator, a Shure 55s, a Heathkit FM3, and a V-M 710 hi-fi tape recorder. Located in the same Michigan city as Heathkit, the V-M Corporation designed and manufactured quality record changers and audio equipment for both OEM customers and consumers, like me. Although the V-M Corp succumbed to overseas manufacturing by the 1970's, its parts and documentation business survives to this day, carried forth by dedicated V-M fans.
In 2000, a newsletter published by the current leadership contained an interview with the last chief engineer of V-M; in it he recalls some contract work V-M did for RCA... er, CBS... well, you'll see in the following paragraph from the newsletter.
One funny story is from the 1950ís when color TV was being developed. RCA at the time was working on a three color disk that would mechanically spin in front of the picture tube. That meant the set had to be about twice as wide as a B&W set. So Don Morrison and some of the R&D engineers got the idea to make the color disk more like a drum, that would spin around the unit. The only problem was to keep in sync with the picture, they had to crank up the speed to the point where it blew up on them! Parts were flying all over the laboratory, so they had to give up on that one. CBS was pursuing an electronic solution with the 3 color guns that we have today.
Ah well. Not withstanding the juxtaposition of RCA and CBS in that interesting bit of television history from the V-M perspective, here's a warm CT-100 glow to the past and present -- the Voice of Music Corp. and the V-M Audio Enthusiasts, LLC .
--Pete (loyal V-M customer and fan)
The date this program was broadcast is in question. Was this the first scheduled color Howdy Doody broadcast or a color demo? If you can contribute to this puzzle, email me. Thanks, Pete
The first NBC color Howdy Doody broadcast was live.
It happened between 5:30 and 6:00 pm each evening. Although Howdy Doody programming goes back to 1947, it was September 12, 1955 that the show went color. That was even before b&w video tape. But fortunately, a kinescope of an early color show exists. Here is my three-minute condensation of that show, highlighting references to color. According to Ed Reitan's History of Color Television, a new color studio was prepared for the show. In the clip, Bob Smith makes reference to their new clubhouse, perhaps a reference to their new color studio.
The clip is a 5-meg video file for a realplayer.
Pete's three generations of RCA color television hardware.
On the right of this little cell picture, the first RCA color set. Made in Bloomington, Indiana in late March 1954, it cost $1000 1954 dollars. It weighed 165 pounds. It has a "15-in." screen that's actually 8.5 by 11 inches.
On the left is the first RCA high definition television set with its huge and heavy 38-in. wide-screen CRT. It was made June 2002 in Mexico. Cost about two-thousand 2002 dollars. Weighs in at 216 pounds without the stand. Its screen is 19.5 by nearly 34 inches.
And the baby of the bunch running there on the floor is special why? It has a flat screen CRT with both NTSC and ATSC tuners, and it has component (composite too of course) inputs just as its big brother on the left. Made in April 2007 in China, it cost just $119, which is slightly less than the New Jersey sales tax on the hi-def set. It has a "14-in." screen that, coming full circle, is actually 8.5 by 11 inches.
Six degrees of separation aren't needed to connect these early electronic events.
More on the NBC color Howdy Doody broadcasts.
Thanks to Bob McGarrah for this composite of scans from two TV Guides in his collection (October 8th and October 22nd, 1955) from central Illinois. Bob writes, "Howdy wasn't carried on our local NBC station, channel 43. It was shown in Springfield on channel 20 but interestingly not in color as of the week of October 10th. However, channel 20 does list Howdy in color beginning on October 24th and with expanded program descriptions. I presume that is when they must have upgraded their transmitter to enable network color."
Thanks to John (
on AudioKarma; that's John and Hillary with Buddy the guinea pig seeing himself on TV
) for this cool vintage-color-TV-ad parody.
The Future of
Blip on top of the CT-100 is the ATSC-to-NTSC converter box the government subsidizes.
Here is the future of analog television. Born only six years after the transistor, and force-fed from a microchip-rich converter box, the venerable CT-100 chugs on.
As planned, video from the converter box runs into the vintage 12AT7-based RCA-design composite video interface, while audio is received on channel 3.
By not connecting audio from the converter box to the audio section of the CT-100, the RF/IF is used, so virtually all the CTC2 circuits are functional except the second detector diode (1N60) and a very few associated components. Feels better that way.
First thing I noticed was an apparent consistency of color, due I suppose to the tight control ATSC has over color space. Here ATSC orange is being reproduced by 1953 NTSC hardware.
On the eve of ETF 2008...
Another Operational CT-100 :-)
Needs a little convergence work, matrix alignment,
screen, background, blue and green video drive set-up,
and a general eyeball tune-up, but operational nonetheless!
See you at the convention this weekend... May 3 to 5, 2008.
[CLICK to RETURN to restoration menu]
[CLICK to RETURN to News & Notices]