View Full Version : "Color socket"--what was it used for?


Jeffhs
04-12-2014, 03:50 PM
Years ago, I had a book with service information on several makes of early 1950s black-and-white televisions. The rear chassis views of some of these sets showed what was referred to as a color socket; the service info called out the correct voltages to be found at certain pins on that socket. What was this used for? Did some TV manufacturers of the '50s make an optional, outboard color adaptor for their black-and-white sets that plugged into the color socket? If so, I would expect any color adaptor of that period would have almost had to be designed for the CBS color system using a color wheel, as the RCA all-electronic NTSC color system didn't appear until much later.

Thanks for any and all replies.

Eric H
04-12-2014, 04:08 PM
I've heard two different reasons for the socket.
One was so that the B&W set would be able to receive the incompatible CBS sequential Color broadcasts (that never happened).

The other reason was that it was for an external color wheel system so a B&W set could be converted to color.

Which is correct? I don't know, but most of the sets with a socket seem to have been made around 1951, or just before the CBS system was set to launch.

David Roper
04-12-2014, 04:10 PM
Yes, such sets would have been made circa 1951 and the proposed adapters (in practical terms they were nonexistent) intended for plugging into those sockets used a rotating wheel with segments of red green and blue translucent filters. Per the CBS system each segment would pass in front of the screen as its corresponding color field was being traced.

More here: http://www.earlytelevision.org/cbs_color_system.html

wa2ise
04-12-2014, 04:42 PM
It was mostly a marketing ploy. Often, there was nothing wired to the socket. And I don't think anyone actually made the adapters in any real quantity. And when NTSC color came out, it turned out better and cheaper(!) to buy a color TV set. Coupled with the lack of a lot of color programming, few people even thought about it.

It was somewhat similar to radio sets claiming to be "Television ready" when they had an audio input jack on the back. As if TV sets were not gonna have audio amps? :scratch2:

cbenham
04-12-2014, 11:29 PM
I've heard two different reasons for the socket.
One was so that the B&W set would be able to receive the incompatible CBS sequential Color broadcasts (that never happened).

The other reason was that it was for an external color wheel system so a B&W set could be converted to color.

Which is correct? I don't know, but most of the sets with a socket seem to have been made around 1951, or just before the CBS system was set to launch.

If the set with the socket was an Admiral or a CBS Tele-King, an Admiral color adaptor model CA-101 could be installed under the chassis of these sets. The CA-101 would adapt the set to receive and display either NTSC or CBS color signals *IN BLACK AND WHITE ONLY*. The socket was for a color wheel system [supplied by others] for use with the set to display the CBS signals in full color. Admiral never made a color wheel for thses sets but Webster-Chicago did. There are images of the W-C color wheel in use in several 1950s TV repair books.

Jeffhs
04-13-2014, 01:27 AM
I don't remember anymore what makes of TVs had the color socket; the small spiral-bound books I had with the service info and color-socket voltage readings are long gone, lost in a move 40+ years ago. :no:

It's interesting to me that some sets had the color socket simply for show, not connected to anything under the chassis, on the rear chassis apron. If this was simply an advertising stunt, I bet anyone who tried to connect a CBS color adaptor to a TV equipped with such a socket was very disappointed when he or she turned the set on and saw the same old black-and-white picture they had been used to for years, or else they thought the adapter itself was faulty; they were probably even more disappointed when they would call a repairman in, who would tell them point-blank that the so-called color socket was not connected to anything and that the customer had bought the color adapter for no good reason.

I doubt that anyone would tolerate having a huge color wheel in their living room, spinning in front of their TV. It would have been OK for an evening, I guess, but I don't think anyone would put up with it much longer than that. Something like putting four stereo speakers in your living room in the early 1970s and sitting on a hard chair in the middle of them so you could get the full 4-channel, quad-sound experience with the then-new and ill-fated quadraphonic stereo system. It was okay for one night, but no one would tolerate it any longer.

If the color wheel were inside the TV cabinet, however, it would be different, but since the CBS color system was so short-lived it really didn't matter. The CBS color-wheel system was probably, even likely, doomed to failure from the beginning anyway, in part due to the large color wheel and also because the system was not compatible with existing black-and-white sets; this meant that CBS color programs could not be viewed directly as b&w on sets without the converter.

RCA's all-electronic NTSC color system, which was compatible with existing black-and-white televisions, however, was a vast improvement over the CBS system, since the RCA system did not require the use of a color wheel or an external color adaptor on the set to receive color programs in color; further, color shows could be viewed on older, existing b&w televisions--in black and white, of course.

Jeffhs
04-13-2014, 02:06 AM
It was mostly a marketing ploy. Often, there was nothing wired to the socket. And I don't think anyone actually made the adapters in any real quantity. And when NTSC color came out, it turned out better and cheaper(!) to buy a color TV set. Coupled with the lack of a lot of color programming, few people even thought about it.

It was somewhat similar to radio sets claiming to be "Television ready" when they had an audio input jack on the back. As if TV sets were not gonna have audio amps? :scratch2:

I remember reading somewhere, don't recall where, that some pre-war TV sets did not have self-contained audio stages or speakers and were to be connected to external audio systems, such as the audio amp and speakers of a console radio, which acted as the TV's sound system. The same reasoning applied years later to radios that had a radio-phono selector switch and an RCA jack on the rear of the chassis; this was meant to be used with an external record changer, so the user could listen to records (at first only 45-rpm ones, as one of the first mass-produced record changers designed for such use was RCA's single-speed 45-EY-3). The changer did not have its own amplifier or speakers; the unit was to be plugged into the phono jack on the back of the radio and listened to over its audio system. Many TVs of the '50s had a similar socket and switch arrangement to allow the use of the set's audio system with a record changer; the arrangement worked, but in many cases the selector switch was on the rear chassis apron and was difficult to operate. The TV-phono selector switch was wired such that, when in the phonograph position, it would black out the raster on the CRT and possibly also remove B+ voltage from any tubes not required for audio. This switch may have been responsible for TV problems such as no raster, if the switch contacts became tarnished or outright dirty or if the switch itself was defective. I wouldn't be surprised if some repair shops simply cut the switch out of the circuit when it went bad; after all, by the '60s, many people had separate high-fidelity systems, newer TVs, and had relegated the old set (if they hadn't junked it by now) to rec room service--there was no longer any need to use the TV as an audio amplifier. My folks' first TV was a 1954 21" RCA console; they also had the matching 45-rpm record changer. Both are long gone, and even if I still had the changer, it wouldn't be of much use to me as the cartridge was missing as late as the 1980s; besides, I don't have any 45-rpm records anymore. I do have a Zenith C-845 AM-FM high-fidelity radio (the set in my avatar) which has a radio-phono selector and RCA phonograph input jack on the rear of the chassis, but that switch hasn't been moved off the radio position in years or decades. It's probably dirty as all get out now, but as long as the radio works (which it does, and well), I couldn't care less if that switch freezes in the radio position.

Steve McVoy
04-13-2014, 07:25 AM
Several prewar sets, including the RCA TT-5 and GE HM-171 had no audio amplifier stage or speaker. A RCA jack connected them to radios for the audio.

Philco experimented with wireless sound:

http://www.earlytelevision.org/wireless_tv_sound.html

cbenham
04-16-2014, 04:49 PM
i doubt that anyone would tolerate having a huge color wheel in their living room, spinning in front of their tv. It would have been ok for an evening, i guess, but i don't think anyone would put up with it much longer than that. Sets; this meant that cbs color programs could not be viewed directly as b&w on sets without the converter.


ha!

Username1
04-16-2014, 06:56 PM
Does anyone remember the Popular Science magazine with the color converter on the cover ? They were lowering a B&W 19" or 17" behind this square converter the picture on the screen was color on the lower half, and B&W where it was above the converter screen....

They showed the insides of the converter, and it was layered plastic belts, Like 19" tall cling film, with B&W and Color lines on them, and they moved pretty slow as I remember, but since they were lines on a full size belt, it was no larger than the tv screen plus 4" on the bottom for the motors and electronics.... 1970's Early I would have to say....

Sorry I forgot I was on the internet.......
http://www.ebay.com/itm/like/380829326527?lpid=82

Anyone ever run into one of these....?

Seen one....?

Here I found it on google books.... Good reading, I really wanted one when I saw it !

http://books.google.com/books?id=fQEAAAAAMBAJ&pg=PA45&dq=popular+science+color+tv+converter+dec.+1971&hl=en&sa=X&ei=zBpPU5PsK9O2yATrhIHIBA&ved=0CC4Q6AEwAA#v=onepage&q=popular%20science%20color%20tv%20converter%20dec .%201971&f=false

I forgot how large the classified section was in PS back then..... Wonder if I can still order a set of X-RAY glasses....?

Anyone ever have one of those 120 in one experimenter kits from Radio Shack....?

See those full page ads to become a TV Repair Technician....?

.

Bill R
04-17-2014, 04:48 PM
I remember that article. The system only used two colors instead of three. I think they used cyan and magenta. flesh colors were ok, but with no yellow the other colors were not quite on par with a color crt. The relatively high ($495 I think) price tag didnt help. Still it was a novel idea. I think it was a Canadian company.

bigaudioal
04-18-2014, 08:30 AM
I have two early 50's Admiral sets. Both have this socket on their chassis. The 21K1's socket is fully wired and has a shorting plug inserted into it. The 21L1's socket is not wired to anything in the set, but the socket is there.

Steve D.
04-19-2014, 10:26 AM
Found these photos buried in my files. This notice and the socket plug were located on the back of a 1951 CBS-Columbia B&W receiver. You'll notice that above the socket plug the words "COLOR SOCKET" are etched into the metal.

-Steve D.