GEC PABX 3+10

STANDARD FEATURES
Maximum capacity
3 public-exchange lines.
10 extension lines.
Connect circuits
Provision for 2 simultaneous inter-extension calls in addition to a maximum of 3 public-exchange calls.

Numbering scheme
00 to 09 for extensions; single digit other than 0 for tie lines.

Public exchange service
Outgoing:
direct access from extensions after operating a pushbutton switch on the telephone.  Individual extensions can be prevented from dialling public-exchange calls.

Incoming:
No operator's switchboard is required; a call is answered at one of up to 4 designated extensions and routed to the required extension by the enquiry and transfer method.  The call can be offered to an extension already engaged.

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.

Executive's priority
Selected executives can break into an existing conversation by dialling an extra digit '1'.

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

OPTIONAL FEATURES
Tie lines*
1 or 2 on one route only.

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

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.

GENERAL
Mode of operation
Fully automatic operation using uniselectors and relays.  All conversations secret from each other.

Tones and ringing
Mains-supply derived dial tone, ringing tone, ringing current and executive intrusion tone; electronically derived busy, number-unobtainable and link throw off tones.  When the exchange operates from a battery power supply, all tones and ringing current are provided by an all-electronic tone generator.

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

Alarm
Audible indication of blown fuse.

Power unit*
Built-in AC power unit: Input, 100 to 120V or 200 to 250V 50 to 60 Hz single phase.
or
External Battery: 50V 32 AH ; with float charger, input as for AC power unit, output 50V d.c 3 A.

Line loop resistance
Not to exceed 1000 ohms.

Construction*
Wired-in units on a steel framework in a floor-mounting steel cabinet (painted dark green) with lift-off dust-proof panels front and rear.

Dimensions and weight

*To be specified when ordering

1975

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

See also GPO PABX 5

Last revised: 18 November, 2000