This is a rare, digitally enhanced photo of the NBC Radio Master Control board from 1933…the year RCA and NBC moved into 30 Rockefeller Plaza.

In the beginning, Studio 3H was radio studio, just one of six medium sized spaces on the 3rd floor, which were about half the size of 3A and 3B. At the time, there were roughly 30 NBC radio studios in the building, but RCA had plans for 3H.

In late 1935, two years after Radio City opened, NBC Radio Studio 3H was converted to RCA Television Studio 3H and technically, would remain an RCA domain until 1939, at which time W2XBS and this studio were put under the control of NBC Television.

It was done under a blanket of secrecy. This mysterious new space was kept secret due to competitive developments for a year, while low key experimental broadcasts from 3H were done, but by early in 1936, RCA decided to go public with the news of their electronic television operations.

After the experimental public broadcasts were started with the three live Iconoscope cameras, RCA also took over a space on the 5th floor for film and called that new area Studio 5F, which was linked to the 3H control room.

Until 1951, 3H was used for experimental and regular programming, and was NBC’s only permanently equipped studio till radio studio 8G began television trials in 1946. Some of the earliest network shows from 3H were “The Kraft Music Hall,” “Television Scene Magazine,” “The Howdy Doody Show” and more. All these shows started out in 3H with the big Iconoscope cameras, and in April of 1948, 3H finally got the new RCA TK30s. The next month, 8G was converted to television.

In 1951, Howdy and the other shows done here moved out, and 3H would become the home of the experimental color tests after the Wardman Park color tests concluded in Washington. The Wardman color cameras were not installed in 3H, however the Washington color veterans were brought from there to continue color tests with the new “coffin cameras.” The joke was, these huge new umber gray cameras were big enough to bury a man in. These were the predecessor to the TK40s and this is the first appearance of the rounded top viewfinder. The color tests from 3H, and later, The Colonial Theater were broadcast over RCA’s experimental color station KE2XJV.

Variety like demonstration shows were done weekdays at 10, 2 and 4 and were staged with vivid colored wardrobes and sets. These shows were mostly for the engineers in New York and RCA’s Princeton labs who watched on closed circuit feeds. Not one to ever miss a marketing opportunity though, these shows were also fed to a half dozen custom built color receivers that were on display in the RCA Exhibition Hall in Rockefeller Plaza. In early ’53 these daily shows would move to The Colonial Theater which was where the new prototype TK40 cameras were beginning to be tested.

After the color tests left for the Colonial, 3H was still involved in color monitor tests, but even then, it stayed busy with regular 15 minute daily programs and live commercials coming from the studio with TK30s wheeled in from Studio 3B.

In the summer of 1955 3H was closed as construction crews took out the wall between 3H and 3F to create the first color studio inside Radio City. The new studio was to become 3K and with a double debut, both Studio 3K and Howdy Doody went to live color the afternoon of September 12, 1955.

Today, 3K is used by MSNBC and is the home to most of their hosts after 7PM, including Chris Hayes, and Lawrence O’Donnell. There is more on the photos, so click through! Enjoy, and there is more to come on 3H. -Bobby Ellerbee

NBC radio studios on the third floor, as they were in 1933

Inside Studio 3H, notice the control room on the 4th floor. To help get your bearings in today’s configuration, the main hallway is behind the photographer taking this.

Inside the 3H control room 1936. This space was actually called 4H.  

Miss Color TV, Marie McNamara in Studio 3H with the “Coffin Cameras” This was the experimental version of the TK40 prototype cameras. These were never used at The Colonial…those were the real prototypes and were silver.

This is a rare color shot of the RCA Exhibition Hall on 49th Street, across from 30 Rock, where the closed circuit color shows could be seen by the public. In 1952, this became home of the “Today” show.

This is me kissing the floor of this hallowed ground. To my right is where 3H was, and the white line is about where 3H and 3F came together to make 3K.

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