TELEPHONE - TABLE
Automatic table telephone for one local and one exchange line

DF310
This telephone can only be used in connection with Switchboards, Type OL, equipped with special line relay sets.

Parts:
Dial RG 112,
Dial cord RS 5062,
Condenser RS 260, 1uF,
Handset RE 1041 of black Bakelite with removable capsule transmitter
RC 40001200, 200ohms, and cord RS 5080.
Bell of 1000ohms.
2 press buttons (1 red and I white).
Case of black Bakelite.
Bell box with 1000ohm bell.
2 condensers RI 260, 1uF.
Line cord RS 9951.
Case of black enamelled sheet iron.

Dimensions:
Height 140mm, width 233mm, depth 175mm.

Weight inc bell box 3.6 kg.

One public exchange line and one line from a private exchange, Type OL, can be connected to this telephone. The public exchange may be on the LB or CB system. The telephone is connected to the public exchange line by pressing the red button and to the private exchange by pressing the white button. The bell of the telephone will ring for calls from the main line and that of the bell box for local calls.

Conversations on one line cannot be overheard on the other. When a call comes in over the public exchange line the red button is pressed and conversation can take place. If the call is to be transferred to another telephone connected to the private exchange, the latter is called by means of the white button and the dial, and the call is transferred by replacing the microtelephone of the first telephone which is disconnected at the same time.

If the called party is engaged or does not answer the operator can return to the exchange line. For this purpose the red button is pressed to bottom position. The local line of the operator's telephone is engaged only during the transfer of calls; when this has been
carried out the telephone can communicate with the private exchange line as usual. This telephone can be used as a wall set by means of a bracket RK 5010.

Taken from the L. M. Ericsson Catalogue No. 188 (1934)

Circuit diagram - 138269.

Last revised: June 08, 2024