Telephone No. 262CB was a combined handset telephone and Repeater Telephonic (amplifier) for customers with weak voices.  The phone could be fitted with a dial if required.  The telephone is a modified Telephone No. 226.

The amplifier unit is secured beneath the telephone in the place normally occupied by the bell-set of a combined telephone set and has a moulded cover similar to a bellset cover but modified to accept the amplifier switching key.

The amplifier has a single stage employing a miniature directly-heated pentode type Hivak XY.  It is operated by dry batteries housed in a battery box which also contains a bias resistor and capacitor.  The degree of amplification is variable and controlled by a potentiometer mounted on a bracket fixed to the telephone cradle.

A Bellset No. 26 was used for the incoming ring and this would be mounted on an adjacent wall.

Available for table use only.

A Dial, Automatic No. 10 could be fitted if required.

The battery box was installed close by.  The batteries required to operate the amplifier were:-
LV - 2 x Cells Leclanché DR2.
HV - Battery Dry No. 2.

Introduced circa 1952, but no indication of it's life span or uptake.

Superseded by the Amplifier No. 143A in 1961.

Circuit Diagram SA4117.

Drawing - 90347

Specification - D1944.

Superseded by Amplifier No. 143A which is used with a Telephone No. 710.

Additional Pictures

The test sets were made up using a Telephone No. 226.
Picture taken in 1937 at the GPO Laboratories at Dollis Hill, London


Picture taken in 1937 at the GPO Laboratories at Dollis Hill, London


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Last revised: June 22, 2023