The LST No. 11A, sales name Facilityphone 200, is a press button electronic table top telephone offering numerous facilities which include:-

  • Hands free loudspeaking telephony

  • Up to l0 digits including

  • 10 direct access repertory dial stores

  • 40 short code dial stores

  • LED digital Display for clock, call timing and calculator.

The telephone contains six rechargeable batteries capable of retaining the memory and powering the electronic dial circuit for approximately 48 hours should the mains supply fail. The battery is automatically recharged by a Plug Top transformer when the mains supply is reconnected. Only calls to and from the telephone handset are possible, during power failure. Should the battery also fail, it will then only be possible to receive incoming calls and the memory store may corrupt.

To extend the period of memory retention, but not give keypad operation during prolonged power failure, it is possible to fit "3 x Silver Oxide" primary batteries, type 10L14 or RW22. These are not supplied with the instrument as they are not necessary for normal operation.

Made by Plessey Office Systems Ltd, Beeston, Nottingham.

Approval Number S/1000/3/D/021594

Sales Catalogue - CP/MS187

A 240 volts, 13 Amp, 50 Hertz Supply is required for the Plug Top Transformer.

The LST No. 11A is suitable for use on Phone Socket installations on DELs and most types of PBX/CCS two wire extensions. Not suitable for use on "C" wire PMBXs or WB 900.

The No. LST 11A has a REN of 1.

LST No. 11A is no longer available, withdrawn from the BT Product Supply portfolio in 1989.

BT then held a number of LST No. 11A's in central depots for maintenance use due to the following situations:-

  • to enable maintenance of the rental base to continue until November 1989.

  • to meet requirements of BT customers with Servicecare maintenance contracts until 1 November 1989 or until their 12 months minimum period expires whichever is the first.

  • to meet warranty returns until March I990.

After a power interruption the LED display can take up to one minute to reset as the display only resets w hen the minute digit changes or the RS button is pressed.

When setting the time clock, timing starts on the release of the RS button.

The user must change the rechargeable batteries every three years and the Silver Oxide batteries every two years, if fitted.

DESCRIPTION                                     BT PART No
Loudspeaking Telephone 11A Stone                411168
Plug Top Transformer. (FF200)                   877618
BACK Home page BT/GPO Telephones Search the Site Glossary of Telecom Terminology Quick Find All Telephone Systems

Last revised: April 29, 2023