TELEPHONE No. 311

Introduced in 1948, this Bakelite cased, combined handset wall telephone (equivalent to the table Telephone No. 310) was used by the BPO in automatic areas on shared service lines with selective ringing and metering.

The handset is a Telephone No. 164.

The telephone had a single press button situated above the dial and above the button was a Label No. 252Q, stating "Call Exchange".

The phone has an integral relay, that stopped bell tinkle and two rectifier units. These components are also fitted in a Bellset No. 41A, which was always installed with the table equivalent model, the Telephone No. 310.

Produced in the colours; Black, Chinese Red, Ivory and Jade Green.

Mark 1 & Mark 2 models never existed. The Mark 2A has a Receiver, Inset No. 2P in the handset.

The phone case is released from the back plate by one screw on the right hand side of the case. The whole body, complete with chassis, swings open to the left, away from the back-plate which is fixed to the wall. The back plate on this telephone has pressed standoffs for the wall mounting.

This phone was superseded by the Telephone No. 321, which was fitted with a Thermistor (which replaced the relay and rectifier packs). The Thermistor is is a very small component compared to the relay and rectifiers, which greatly reduced the cost of the phone.

It was also superseded by Telephone No. 711 in 1964.

Supplied to the BPO by British Ericsson, their models:-
Telephone No. 311F - No. N1071D1.
Telephone No. 311L - No. N1071D2.

Telephone Includes:-
1 x Bell No. 59A, Unmounted.
1 x Bell-gong No. 2.
1 x Bell-gong No. 2A Nickeled.
1 x Coil, Induction No. 27.
1 x Capacitor, M.C. No. 97.
1 x Capacitor, Paper No. 7510.
1 x Cord, Instrument No. 5/28E, 10".
1 x Dial, Automatic S.S., No. 10LA or 10FA.
1 x Key No. 302B.
1 x Label No. 252Q (Colour).
1 x Rectifier Element No. 4/6A.
1 x Rectifier Element No. 1/12A.
1 x Relay No. 8552.
1 x Part No. 2/DCA/89 (Colour).
1 x Telephone No. 164 Mark 2 (Colour).