GEC PABX 10+98/16+97

GEC-AEI TELECOMMUNICATIONS LIMITED
A Management Company of The General Electric Company Limited of England

10+98/16+97 Line Private Automatic Branch Exchange

STANDARD FEATURES
Maximum capacity
10 public exchange lines and 98 extension lines; can be extended to 16 public exchange lines in which case the number of extension lines is reduced to 97.

Connect circuits
Provision for 10 simultaneous inter-extension calls in addition to a maximum of 10 or 16 public exchange calls.

Numbering scheme
Within the range 200 to 299 for extensions; 7 for tie-line access; 8 for night service; 9 for public exchange access; 0 for operator switchboard access.

Public exchange service
Outgoing: direct access from extensions, or through operator's switchboard. Individual extensions can be prevented from dialling public-exchange calls.
Incoming: through operator's switchboard.

Enquiry and transfer
Telephones with a pushbutton can be supplied to all or selected extensions to enable a public exchange call to be held while the user calls another extension with an enquiry.  When the enquiry is complete, the original extension returns to the public-exchange call, or can transfer it to another extension or to the operator.

Night service
Incoming public-exchange calls can be answered from any extension by dialling '8'; alternatively, the feature can be restricted to one extension only*.  Calls can then be transferred to other extensions by the enquiry and transfer method.

Trunk offer
The operator can offer a public-exchange call to an extension already engaged.

Executive's priority
A maximum of 10 selected executives can break into an existing conversation by dialling an extra digit '1'.

OPTIONAL FEATURES
 Tie lines
Up to 4 on one route only.

Conference
Designated extensions can be connected together via a special circuit.

Fire alarm
Various procedures are available to suit individual requirements and local fire regulations.

Staff location
Staff absent from their offices may be called by dialling a special locating number and a personal code, to operate lamps or bells.

Secretary service
A secretarial switching telephone enables secretaries to filter calls to an executive.

Route restriction
Individual extensions may be permitted to dial local but not long-distance calls.

Mains-fail protection
Public exchange lines can be automatically connected to designated extensions in the event of an AC mains supply failure.

GENERAL
Mode of operation
Fully automatic operation using 2-motion selectors, uniselectors and relays.  All conversations secret from each other.

Tones and ringing
All-electronic tone generator provides dial tone, ring tone and current, busy tone, number-unobtainable tone and operator/executive intrusion tone.

Signalling
Required dial-pulse characteristics: 7 to 14 i.p.s., 2:1 break to make ratio.

Alarms
Lamp indication at switchboard.
Urgent: release alarm, ring fail and blown fuse.
Deferred: failure to replace receiver (PG condition).

Power unit
AC power unit: input, 100 to 120V or 200 to 250V 50 to 60Hz single phase; 50V d.c., output 10A for 10+98 line, 15A for 16+97 line.
or
Battery: 50V 48 AH; with float charger, input as for AC power unit, 50V d.c., output 5A for 10+98 line, 10A for 16+97 line.

Line-loop resistance
Not to exceed 900 ohms.

Construction
Switching equipment: Plug-in and wired-in units on a steel framework.  Optional rack-enclosing cabinets (painted grey) with lift-off dust-proof panels front and rear can be provided.
Switchboard: dual grey desk-mounting console.

Dimensions and weight

Taken from a GEC-AEI brochure SLX11B - dated 1968

Last revised: November 30, 2021