PLESSEY PBT 400 TELEPHONE
PBT 400 PBT 401


Plessey PBT 400 - The Fully Electronic Telephone

Designed for today with the future in mind, Plessey PBT 400 has a  performance that matches its elegant styling.

Plessey PBT 400 is part of Plessey’s comprehensive range of advanced electronic telephones that satisfy the needs of both the business and domestic user.

Features
Plessey PBT 400 has a streamlined elegant style and is available in a range of colours.

Plessey PBT 400 employs the use of electronic speech circuits and electromagnetic transducers. The electronic signalling circuit provides last number redial and a 10-number repertory memory. On hook dialling with two-way amplifier enables full handsfree operation. An elastomeric keypad of the latest design and an electronic tone caller with volume control are also provided.

The major fault-prone areas of conventional telephones have been eliminated, leading to absolute reliability and extended operating life.

Plessey PBT 400 can be easily installed on direct exchange lines, PABX extensions and in extension plan arrangements.

  • Executive styling

  • For home and office

  • Fast pushbutton dialling

  • Last number redial

  • 10 number repertory

  • Handsfree loudspeech

  • High reliability

  • Easy installation

  • Free standing or wall mounted

To meet the needs of international markets Plessey PBT 400 can be supplied with the line cord terminated with a British Telecom Plug 431A or in stone only with a standard desk block.

Colours
Stone with matching stone cords, light grey, light green and off-white - all with light grey cords.
The facility buttons are highlighted by a contrasting grey feature panel.

Outline Specification
Approximate dimensions
Height 117mm (4.7in)
Width 160mm (6.3in)
Depth 2 16mm (8.5in)

Keypad
Silicone elastomer type, 10 buttons in 3 x 3 x 1 format for loop disconnect (decadic) signalling, 12 buttons in 3 x 4 format for MF signalling to CCITT recommendations.

Recall
Timed break or earth loop recall can be fitted.

Tone Caller
Dual-tone high impedance type comprising silvered piezo-ceramic disc bonded to a larger diameter thin metal disc with rotary vane acoustic volume control.

Loop Disconnect Signalling
10/20 pps - 2:1/1.5:1 break/make ratio IDP 10 and 20 pps - 800/400 ms.

MF Signalling
1 x 4 plus 1 x 4 VF signalling to CCITT recommendations, with confidence tone.

Last Number Redial
Repeat of last number dialled.

Repertory
Ten numbers stored in memory, recalled by pressing two buttons.

Handsfree Loudspeech
On hook dialling initiated by pressing single button, two way amplifier for monitoring and loudspeaking conversation.  

Transmission
Integrated circuitry handles the signalling and transmission functions, send and receive levels being controlled electronically with regulation applied automatically within the integrated circuit.  

Power
A mains powered DC power supply is included as standard to provide loudspeech and on hook dialling facilities.

Ordering Information
BT Plug 431A Line Cord Termination.

PBT 400 LD, 10 ABB DIAL, LOUD SPEECH, OHD, TONE CALLER. PST LEAD.
PBT 401 LD, 10 ABB DIAL, LOUD SPEECH, OHD, TONE CALLER, RECALL. PST LEAD.
PBT 403 MF, 10 ABB DIAL, LOUD SPEECH, OHD, TONE CALLER, RECALL. PST LEAD.
PBT 481 LD, 10 ABB DIAL, LOUD SPEECH, OHD, TONE CALLER, RECALL. SPADE ENDED LEAD. COLOUR - STONE.
PBT 483 MF, 10 ABB DIAL, LOUD SPEECH, OHD, TONE CALLER, RECALL. SPADE ENDED LEAD. COLOUR - STONE.

 

 
 
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Last revised: July 23, 2025

FM