GEC No. 2100 Series
The combined ringing and speaking keys and separate clearing drop indicators with which these switchboards are fitted enable connections to he effected more conveniently and expeditiously than on switch-hoards of the No. 2000 Series.
The apparatus is mounted in a matt polished walnut cabinet which is hinged to a substantial backboard. This arrangement permits the whole of the front portion of the switchboard to be swung forward giving free access to the apparatus, wiring and line terminals for inspection and maintenance.
The 100 ohm drop indicators in the line circuits are used only as calling signals. A 500 ohm tubular "ring-off" drop indicator and a combined ringing and speaking key are associated with each pair of connecting cords, and a common "ring-back" key is also provided which, in conjunction with the speaking keys, enables the operator to ring back on a calling line if necessary.
An operators telephone circuit is incorporated in the switchboard, consisting of an induction coil and a hand combination telephone having a battery key in the handle.
In order to prevent delay if the operator fails to notice a calling or clearing signal, an alarm bell is fitted, the circuit of which is completed through contacts operated by the drop indicators. A switch is provided so that the bell may he disconnected if desired.
Any of the magneto telephones of the bridging or bridging sure-ring types listed in this catalogue are suitable for use as extension instruments with switchboards of the No. 2100 Series.
Cat. No. 2130 is shown pictured above.
Taken from the GEC Telephones and Switchboards (Manual and Automatic) Catalogue No. 11 (Circa 1936)
Last revised: July 30, 2012