The First Kinescope Images…”Colored Television”, 1933
The First Kinescope Images…”Colored Television”, 1933
Earlier this week, I posted a story on RCA/NBC’s first TV transmissions from the new Empire State Building tower, and mentioned an interesting side story was to come later…here it is.
RCA/NBC’s 85th floor transmitters in the Empire State Building began experimental television transmissions from there on December 22, 1931. Separate transmitters for visual and aural transmissions were used with the call letters W2XF and W2XK respectively.
These two transmitters were operated concurrently with another NBC television transmitter already located at the New Amsterdam Theater studio on 42nd Street. This earlier station carried the call letters W2XBS (later transferred to the Empire State transmitter) and operated on approximately 2 MHz with 60-line, mechanically scanned picture signals, and received on mechanical scan receivers.
The first experimental transmission from the Empire State Building were 120-line pictures using mechanical scanning of both film and live subjects, BUT…these are believed to be the first high-power, high-frequency transmissions received and monitored by means of the kinescope, or cathode-ray picture tube.
At that time, the tubes had green fluorescent screens, since the white phosphor later used for black-and-white television had not yet been developed. The Empire State tests, even though at a line rate twice that of the W2XBS 60-line tests indicated that greater resolution would be required for a satisfactory public television service.
“It’s Not Easy Being Green” -Kermit
The CRT’s back then used the P1 phosphor as oscilloscope CRT’s did. Once they started using the P4 phosphor which was a silvery/white, the entire look changed, but the process for making P4 phosphor was not developed until a few years later.
The CRT numbers showed the type of phosphor used in each, for example…a common 21 inch monochrome CRT with the number 21FBP4 used the silver phosphor (P4). A common oscilloscope CRT was a 5UP1 (using the P1 phosphor…green). P22 was used in color CRT’s, for example a common color CRT was a 21FJP22. The last 2 to 3 digits indicated the type phosphor. P3 Phosphor was orange and P7 with a blue glow was used for radar. -Bobby Ellerbee
I assume this “target” is a Coca Cola ad out of a magazine.
I *believe* I’ve heard of some early portables in the 70s (specifically Thomson and Fernseh; possibly other Euro makes) using CRTs with green phosphor in their viewfinders. I’m sure those who’ve actually seen and used such cameras could confirm…..?
Looks like Kate Smith.
Love this stuff. Never get enuff
My grandfather once told me “The first thing I ever saw on television was Eleanor Roosevelt – and she was green!” But he couldn’t pin down the date. By 1939 all the tubes used “white” phosphors, didn’t they? How white was the white of the 1930s?