Museum Hours:

Saturday 10-6

Sunday 12-5

Mechanical Television

Bell Labs Matrix Screen Receiver

In 1927 Bell Labs built a large screen TV set using a specially designed neon lamp with 2500 individual anodes, arranged in 50 rows of 50 anodes. A huge switch was attached to the motor, routing the electrical signals to one anode at a time. This set was used to televise Herbert Hoover in a demonstration in April of 1927. This was accomplished both by wire and by radio on experimental station 3XN from Whippany, N. J., 22 miles from New York, to the Bell Laboratories building in New York City where the speakers and performers were readily recognized on the receiving screen. The voices of the persons at Whippany were transmitted, and reproduced by means of a loudspeaker. Here is a 1928 magazine article.

The screen as it appeared in 1927

Here is a photo from 1927 of the motor and switch assembly

A modern photo of the side of the cabinet. The screen is facing toward the right back

The screen, showing the individual bulbs



The right side, with the door open 


The left side of the cabinet, with the door open, showing the motor and switch 

Detail of commutator

Practical Radio, 1928

Courtesy of Gabe Bennett