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Tandy Radio Shack TRS-80 Acoustic Modem

Acoustic Coupler AC-3

A standard telephone handset was placed into a cradle of the acoustic modem that had been engineered to fit closely (by the use of rubber seals) around the microphone and earpiece of the handset. A modem would modulate a loudspeaker in the cup attached to the handset's microphone, and sound from the loudspeaker in the telephone handset's earpiece would be picked up by a microphone in the cup attached to the earpiece. In this way signals could be passed in both directions.

Sold for $149.95. Advertised as being ideal for travellers! Just dial the desired number and place handset on interface. Half duplex also. Sensitivity: -43 sBm. 2-3/8 x 4-3/4 x 10-1/4".

Catalogue No: 26-1174-A
Serial No: 119558

Comes with 'TRS-80 Acoustic Modem Operation Manual Catalog Number 26-1174A'.

Our Model kindly donated by Peter Martin.


Date : 1985

Manufacturer : Tandy

Physical Description : Acoustic modem AC adaptor Operation Manual

This exhibit has a reference ID of CH13105. Please quote this reference ID in any communication with the Centre for Computing History.

Scan of Document: Tandy Radio Shack TRS-80 Acoustic Modem

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