SWITCHBOARD No's N111 & N112
C.B., CORDLESS, PRIVATE BRANCH EXCHANGE
This switchboard occupies less space than a typewriter, has a sloping front to afford maximum visibility for operating, and can be opened (see illustration) to give easy access to all the parts.
Components have full tropical finish and connecting wires are p.v.c. insulated.
The cover has black or biscuit colour plastic ends and mottled grey-green enamelled aluminium centre sections. The metal base is deep Brunswick green.
Keys are new miniature type. Each vertical row can be removed as a unit for spring adjustments. The plastic key handles differ in colour for keys of differing functions and have an insert of a contrasting colour in the tip to render operated keys easily discernible.
Indicators are new twin-shutter type with dust-excluding plastic windows. The non-locking extension indicators give positive supervision. Exchange indicators lock to ringing current and are restored by pressing down on the projecting top of the window.
The operator's circuit (1000 ohm loop type) includes a plug-in handset with rocking-armature receiver. The generator is of rotary magnet type; relays and retards are N. 30000 type.
The battery fuse fitted below the handset can be replaced without removing the switchboard cover.
For auto, a dial with any specified numbering or imputing can be supplied. A switchboard is converted to automatic by replacing the plain front plate by one incorporating a dial.
Line wires terminate at screw connections in the board. Alternatively, a desk cord and terminal block can be supplied as extras.
Orders for boards should state Type No., colour of ends and length of desk cord if required, e.g. N112B (biscuit) with 6 ft. desk cord and block.
Operating Voltage 24 volts D.C. (nominal).
Busy Hour Current Drain Approx. 0.4A for 6-line and 0.6A for 12-line boards.
Taken from the Ericsson catalogue, edition No. 55
The N111 (2+4), N112 (3+9) switchboards were also by the Irish P&T.
All were supplied in two-tone grey.
Last revised: October 12, 2019