TELEPHONE No. 80

Metal and Plastic cased hand held test telephones for use in telephone exchanges.

Fitted with press switch and on the metal variants, a loop suspension.

No dial is fitted to any of these telephones.

Picture to the right shows a Mark 236 (1928 model).

Telephone No. 80A - Handset telephone similar to No. 80 but provided with a separate speaking battery feed to permit its use on dry loop circuits. Required initially for maintenance officers on 2 V.F. circuits.

Telephone No. 80B - Plastic handset with microphone press switch. There is no induction coil fitted.

There appears to be no drawings for this telephone and the specification advises the ATM model L11280 should be used as the basis for design.

Telephone No. 80 Mark 4 includes (1928):-
1 x Condenser, M.C. No. 83.
1 x Cord, Instrument No. 249.
1 x Diaphragm No. 12.
1 x Earpiece No. 13.
1 x Transmitter, Inset No. 2.

To be requisitioned separately:-
1 x Plug No. 310, 409 or other suitable plug.

Telephone No. 80 Mark 5 includes (1954):-
1 x Coil, Induction No. 26.
1 x Mouthpiece No. 15 or Mouthpiece No. 18 (Mark 5).
1 x Condenser and Resistor No. 3.
1 x Receiver, Inset No. 1L.
1 x Transmitter, Inset No. 13.
1 x Cord, Instrument No. 2/95F, Black, 48".

Telephone No. 80A includes (1946 and 1956):-
1 x Coil, Induction No. 26 (Modified).
1 x Mouthpiece No. 15 or Mouthpiece No. 18 (Mark 5).
1 x Condenser and Resistor No. 3.
1 x Receiver, Inset No. 1L.
1 x Resistor Coil No. 12 800ohms.
1 x Cord, Instrument No. 2/87F, Black, 48".
1 x Cord Instrument, Special 84".
1 x Plug No. 316.
1 x Plug No. 410.
1 x Transmitter, Inset No. 13.

Telephone No. 80B includes (1962):-
1 x Handset No. 6.
1 x Capacitor 0.5uf.
1 x Resistor, Coil No. 35A 200 ohms.
1 x Resistor Carbon No. 26KD 510ohms.
1 x Receiver, Inset No. 4T.
1 x Rectifier Element No. 205.
1 x Switch No. 5A.
1 x Cord, Instrument No. 2/147AA, Black, 48".
1 x Plug No. 240A.
1 x Transmitter, Inset No. 16.

Circuit diagrams - N180F and N180H.
Circuit diagram - A.T. 205.
Circuit diagram - CD 814 (Mark 5) dated 1951.

Specifications - S109 (Mark 4), S210 (Mark 5) & S613 (80B).

These telephones were superseded by the Telephone No. 280.

ATM made some of these telephones:-
Telephone No. 80 Mk 236
Telephone No. 80 Mk 5
Telephone No. 80A

Telephone No. 80 Mark 5 - Front and back