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1954 RCA CT100 15" Color TV
The Holy Grail of Color TV Collecting

The RCA CT100, named the Merrill, is widely accepted as being the first mass produced color television set.  However Westinghouse had it’s first color television set available for sale a number of weeks prior to the RCA set officially went on sale to the public in April 1954. These photos are of actual RCA Dealer literature promoting the new RCA CT100 Merrill color TV set.

Background of Color Television Development
The race to be the first company selling color television sets was hard fought.  The biggest rivalry was between RCA who had been developing an all electronic system for color, and CBS who was trying to promote, what in retrospect was an absurd electromechanical system, with a spinning color filter wheel in front of a black and white picture tube.  The CBS system did produce beautiful color pictures, however it had a major drawback.  In order to have a 21” color TV set, you would need to spin a filter disc in front of the picture tube that would be about 4 feet in diameter.  And what was worse, when a CBS color broadcast was taking place, you could not watch it on a black and white receiver because the CBS color signal was not compatible with a standard black and white TV set. Due to the complexity of trying to decide which system of color television should be adopted in the United States, the federal government appointed a committee of scientists to study the issue and make recommendations to the government, on which color system to adopt.  That committee was the National Television System Committee. The RCA compatible all electronic color TV system was ultimately adopted, and was thereafter referred to as the NTSC color system.  The whole story is very complex. The color TV system competition trials went on for about 4 years from the late 1949 until late 1953.  There was dirty politics involved in the beginning to pressure congress to adopt the CBS mechanical system, but truth and science ultimately won out.  If you wish to read about the evolution of the early NTSC color trials; Google “Color TV wars” or follow this link to a good discussion about the “Color Wars” written by my good friend Pete Deksnis.  Pete knows more about the CT100 than anyone else I know.   http://www.earlytelevision.org/Deksnis/rca-cbs_color-wars.html

New Years Day, Friday, January 1, 1954
The first national coast-to-coast color telecast was on January 1, 1954.  It was the New Years Day Tournament of Roses from Pasadena California. The RCA CT100 color TV set wasn't available to the general public at the time.  However RCA (and some other manufactures) made a limited number of prototype sets available in public places.  RCA made run of about 200 “Model 5” prototype color sets (similar to the CT100) and shipped those Model 5 sets to NBC affiliates and RCA dealers across the country, just in time for the general public to see January 1st. 1954 Rose parade.  Here in Milwaukee, Model 5 color sets were located at the NBC affiliate studios of WTMJ, and at a couple of RCA appliance dealers, where hundreds of people flocked to see the first ever coast-to-coast color telecast.

American Appliance & TV store at 2743 N. Teutonia Ave. was one of the RCA dealers to allow the public into their store to view the color telecast of the Tournament of Roses Parade.  This is a photo of the crowd waiting outside of the American Appliance store waiting to see color television for the first time.

According to a Milwaukee Journal news article, about 5000 people lined up to get into the store.  There were so many people, that they were let into the store in groups, and only allowed to view the small 15 inch color screen for about 5 minutes.  After 5 minutes, that group was scooted out and another group took their place.  By the end of 1954 there were about 100 color TV sets in the Milwaukee area.  WTMJ Channel 4 was the 17th station in the country to go on the air after WWII, and was 7th local NBC affiliate in the country to receive color broadcasting equipment to originate locally broadcast color programs.  By the end of 1954 WTMJ was broadcasting 40 hours of color programs per month.  WTMJ Channel 4 was one of the nations television broadcasting pioneers, and was always on the cutting edge of the latest technical developments in television broadcasting.

Click this link to see an actual weekly WTMJ programing schedule from September 1954.

How strange it is today that we take for granted that ALL television programming is in color, and that TV is broadcast 24 hours per day.  Back in 1950 when I was 3 years old, regularly scheduled programming did not start until 1PM in the afternoon.  Prior to 1PM all you got was a test pattern.  And programming ended at Midnight with the playing of the National Anthem.

So even though Westinghouse actually beat RCA to the market with the first commercial color TV set, the RCA CT100 Merrill was the color set that was most widely available and that sold the largest number of units. However, the life of the CT100 was short lived.  RCA already had a color tv with a 21" screen in the works. The 21” color set replaced the CT100 15” model about 1 year after it was introduced.  The 21” RCA color set was the model 21CT55.  You can see my restored 21CT55 story by clicking on the link in the restorations menu, or by clicking on this LINK.

The viewing screen of the CT100 was a mere 15 inches wide .  The 15GP22 picture tube was powered by the specially designed CTC2 color TV chassis using 36 vacuum tubes.  The CT100 had a price tag of $1000.  It was a very expensive TV set, considering at the time in 1954, you could by a basic 21” black and white TV for $300 on average.  In addition, in 1954 there were only about 6 hours of color broadcasting each week; and most of that originated directly from the NBC network studios. In 1954 very few local stations had color equipment in their studios. 

ACQUISITION
I started my hobby of collecting and restoring antique TV sets in 2001 with the acquisition of the Hallicrafter Model 820 black and white set.  As do most beginners in almost any collecting hobby, my initial zeal to collect had me collecting almost any kind of TV.  My collecting tastes became more refined and I soon started collecting only sets with round picture tubes.  Zenith Portholes became my favorite.

One winter, while visiting my mom at her Florida condo, I decided to go see the collection of fellow collector John Folsom who also lives in Florida. John’s collection is widely considered to be the best collection of early color sets.  That was enough for me.  I decided that I had to move up from collecting black and white sets, to collecting color sets.  John Folsom likes to say “I went over to the dark side”

Soon after my visit to see John’s collection I had an opportunity to purchase my first “early color” set; an RCA CT100 from Pete Deksnis who was living in Asbury Park, NJ at the time.  Pete had a nice CT100 for sale but it had a bad 15GP22 picture tube.  Even so, as my first early color set, it was a place to start.
I would worry about finding a picture tube later. I did a road trip from Milwaukee to visit Pete, see his collection, and pick up my new CT100.  A couple years later I purchased a second CT100 from a collector in Appleton Wisconsin which also had a bad 15GP22 picture tube.  These photos show the set as it was at Pete’s house in New Jersey.

The 15GP22 Color Picture Tube
The CT100 is a historic technological achievement.  RCA scientists conceived a method of transmitting a standard black and white television signal, and embedding color information into the standard black and white signal, in a way that would allow color telecasts to be viewed on a black and white receiver.  On black and white TV sets the “color information” is simply ignored.  In a color receiver there are special additional circuits that detect the “color information” and combine it with the black and white information to create color images on a specially designed tri color picture tube.  The revolutionary color picture tube that RCA invented is designated the 15GP22.  At the time, having a picture tube that could display Red, Green, and Blue images superimposed on top if each other, to form a full color picture was un-imaginable. But the basic concept of RCA’s tri-color picture tube is in use to this day.  Even flat screen televisions still use miniature color cells imbedded in the screen to create a full picture from 3 primary colors.  In order to deposit red, green and blue colored phosphor dots on the face of a color picture tube, it requires the tube to be constructed in two pieces; that being a front face and a rear section. This is a photo of RCA’s promotional add to the TV industry, announcing the new 15GP22 color picture tube.

Every color picture tube ever made was constructed with a front section and a rear section.  In 1953 when the 15GP22 was invented, materials science had not yet come up with a good reliable method of attaching the front half of the color tube to the rear half.  The only method RCA could devise, was to fuse the glass front section and the glass rear section, each to a metal ring, then bring the two halves of the tube together and weld the two rings together.  This is a photo of one of my 15GP22 picture tubes.  You can clearly see the metal ring near the front of the tube.

This is a photo of the welding process in the RCA picture tube factory back in 1953.  Unfortunately, the process of welding the two halves of the 15GP22 had a drawback.  Often the welds were not perfectly vacuum tight.  In addition, cracks often formed where the glass was fused to the metal rings.  As a result the 15GP22 was highly prone to losing its vacuum.  Very few of the 15GP22 picture tubes have survived.  Most of them developed vacuum leaks and became unusable.  Because of the high failure rate, good, usable 15GP22 picture tubes are very very rare and extremely valuable.

It is said that RCA produced around 5000 CT100 tv sets.  Other manufacturers also purchased the 15GP22 picture tube from RCA for their early color tv sets.  I think we could estimate at most 6000 15GP22 tubes were produced.  Although exact numbers are not known, the number of functional 15GP22 picture tubes is thought to be somewhere between 40 and 50.

Around 1957, a substance called “frit glass” became available.  It is made from powdered glass, trace metals, and certain chemicals.  It is the consistency of tooth paste.  Frit glass can be placed between two precision ground glass surfaces, and when baked in an oven the frit glass will bond the glass surfaces together with a joint that will hold a very high vacuum.  The invention of frit glass solved the problem of joining the front and rear sections of a color picture tube, with a joint that was vacuum tight.  This method of joining the front and rear sections of color picture tubes was used by all picture tube manufacturers until production of picture tubes ceased when flat screen TV’s made picture tubes obsolete.

It took a number of years for me to locate good picture tubes for my 2 CT100’s.  One day I got word through the grape vine that someone in Michigan had a brand new 15GP22 that had been in storage for about 30 years and it was for sale.  I drove to Michigan and met with the seller.  The tube was still in the original RCA shipping carton.  The carton itself is a very rare piece of history.  Here is a photo of the original RCA Factory shipping carton.  You can see 15GP22 printed on the RCA label.

 I tested the tube and it tested as good as the day it left the RCA factory.  Several years later, when the General David Sarnoff library was being closed, the crew that was helping to preserve the artifacts, discovered some long forgotten picture tubes tucked away in a corner of the basement.  One of the tubes was a 15GP22.  It went up for auction on Ebay and I put in a very sizable bid and was the winning bidder.  So now I had 2 rare 15GP22 picture tubes for my two RCA CT100’s.  In 2016 I was able to acquire a third 15GP22.  My collection has 5 of them now.  Enough to populate all of my early color sets that need one.

THE CT100 RESTORATION
About 4 years after acquiring my first CT100 I began its restoration.  The first stage was to remove the chassis, and various other hardware from the cabinet.  Here is a photo of the chassis as it looked prior to restoration.

The cabinet was in need of refinishing so I sent it off to a furniture refinishing shop to be refinished.  Here are the photos of the refinished cabinet and a close up of the original label that RCA placed on the set.

 

 

Chassis restoration was a big job compared to a black and white set.  The CT100 has 35 vacuum tubes, and a lot of associated components. I replaced all the old wax paper capacitors and all of the electrolytic capacitors, in addition to several unreliable power resistors. Here is a photo of the underside of the chassis after re-capping.

The low voltage power supply in the CT100 used selenium stack rectifiers which are very inefficient. Standard practice is to replace these with silicon diodes.  Because silicon diodes are more efficient, it causes an undesireable increase in the DC supply voltages, which needs to be addressed.  To bring the supply voltages back into correct design limits, I added 2, 25 ohm, 25 watt resistors in series with the silicon diodes.  The modifications can be seen in this photo.

The restored chassis was powered up on the bench with a variac and the chassis was connected to a 15GP22 picture tube mounted on a “crt truck” shown in these photos.

After some initial adjustments I had a usable, although less than perfect picture as shown in this photo.  

 

One of the common problem parts of this TV is the fine tuning knob. It has a large diameter plastic throat with a keyway that mates to the fine tuning shaft on the tuner.  The plastic throat on this knob was prone to breaking.  I needed to repair this knob.  This first photo shows the knob with the broken plastic throat on the left and the knob with the broken throat removed on the right. 

I obtained some aluminum thick wall tubing of the correct dimensions and machined a replacement throat to attach to the original plastic throat stub that remained on the knob.  The new aluminum throat is shown in this photo.

Lastly, I used standard epoxy glue to attach the new aluminum hub to the stub on the knob as shown here.

 

I was satisfied that with more adjustments we would be rewarded with a satisfactory picture and decided it was time make final adjustments and install everything in the re-finished cabinet.

To install the picture tube and its associated components, the cabinet is laid face down on the floor as shown in this photo.

 

Then the 15GP22 picture tube is placed inside the front bezel and the, mu-metal shield, retainer ring and strut rods, deflection yoke and purity collar are installed as shown.

 

This photo is taken with the cabinet standing up in it’s normal operating position.  The top of the cabinet is removable for ease of servicing.

 

For final adjustment and checkout, I place a piece of plywood on the top of the cabinet and place the chassis on top of the set as shown in this photo.  I have special extension cables that allow me to connect the deflection yoke, picture tube and other components so that I can operate the set with the chassis sitting on top of the set. 

The first adjustments are for “purity”  Purity refers to a process of making adjustments so that “pure” red, blue, and green color can be obtained all over the viewing screen.  Next comes gray scale adjustments to adjust the brightness level of the 3 colors to create a natural looking black and white picture. 

The next adjustment procedure is called “convergence”.  Convergence is the process of adjusting the three color images so that they are almost perfectly superimposed on top of each other without “color fringing” around the edges of the images.  To aid in convergence adjustments, I use a NTSC pattern generator.  The generator is connected to the antenna terminals of the TV and the TV is tuned to channel 6.  I can set the pattern generator to display dots and cross hatch patterns which help me to do the convergence adjustments.  These photos show the dots and crosshatch patterns. It is not usually possible to get “perfect” convergence across the entire screen.  So you will notice that you can see some “divergence” of the colors on some lines of the crosshatch near the edges of the screen in these photos.

These photos show standard NTSC color pattern and the standard color bar pattern.

 

Once all the adjustments are completed, the chassis is installed in the cabinet as shown in this photo. 

 


Considering the state of electronics in 1954, what RCA achieved with the introduction of the CT100, is nothing short of miraculous!

Baseball, Hot dogs, Apple Pie and RCA.  America..The greatest country in the world!

And here are some photos of the completed restoration and screen shots from “The Wizard of Oz”