Transistorized audio-frequency telephone amplifier, 1955

Made:
1955 in Post Office Research Station, Dollis Hill
Transistorized audio-frequency telephone amplifier

Creative Commons LicenseThis image is released under a CC BY-NC-SA 4.0 Licence

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Transistorized audio-frequency telephone amplifier
Science Museum Group Collection
© The Board of Trustees of the Science Museum

Transistorized audio-frequency telephone amplifier, probably designed and made at the Post Office Research Centre at Dollis Hill, London, England, 1955.

Very soon after the development of successful transistors in 1947, the Post Office Research Station at Dollis Hill, London, were working on their use in telephone repeaters (amplifiers). This is an improvement of a 1953 design of a transistorised push-pull amplifier. With larger and better input and output transformers, it formed the basis of the amplifiers put on a field trial in 1955.

Details

Category:
Telecommunications
Object Number:
1971-438
Materials:
metal (unknown)
Measurements:
overall: 145 mm x 83 mm x 60 mm, .46kg
type:
amplifier
credit:
Donated by BT Heritage and Archives