AB 2321
The frame of pressed black lacquered iron sheet with a cabinet for two round batteries of diameter 65mm and height 170mm.

The telephone consists of:-
Microphone RE 1002 with cord RS 6020.
Five-magnet inductor RH 5505 with laminated armature.
Ringer of 5000 ohm resistance.
Capacitor with 1 microfarad capacity in the speech current circuit.
Two push buttons, one black and one red.
Connection clamps.

The telephone sets are connected in parallel on a two-wire telephone line, and calls are made using different signals. When the black button is pressed, the own ringer is cancelled, so that a stronger signal is obtained on the line. When the red button is pressed, the two line branches are short-circuited to a single line, at the same time the inductor is connected between this single line and ground. Through this device, device no. 1 call no. 16, without any signal being heard from intermediate devices 2-15. The devices no. 1 and 16 must in this case be equipped with voltage divider RM 110 and extra ringer RA 10/500 in accordance with the adjacent diagram, as the signal arrives on the extra clock and not on the device's own clock. Then no. 1 should call no. 2, press the black button and call, e.g. 2 short signals, then no. 2 knows that the signal refers to his device and answers the call.

Taken from the L. M. Ericsson Telephones and Signalling Material Catalogue No. 122 (1930) - Swedish Translation

Last revised: March 25, 2024