TELEPHONE No. 786 & 8786


Basic network, low send level, push button push button Trimphone for use on MF signalling systems.  Based on the Telephone No.2/766 Mark 2 except that a 12 button push button unit and a line powered oscilator replaces the rotary dial unit.

Note the front of the casing is much higher than an ordinary Trimphone, because of the size of the circuit board for the keypad.

Introduced in 1977.

Circuit diagram - N886.

Specification - S1340.

Telephone No. 8786
Introduced in 1982, the Telephone No. 8786 was a Telephone No. 786 modified to work on the Plug and Sockets system.  It was fitted with a Resistor No 91 EJ 3K3 and a Cord Connecting No. 4/504 Light Grey, 3000mm.  The Gas Discharge Tube (Protector 11A) was also omitted.

The 8786RR was fitted with a Timed Break Recall button (Register Recall).



Additional Information
Model Mark Blue Grey Green PBU Introduced Remarks
Tele 786 Mk 1 y y y 52A/1 8/76 STC - was 1/766
  Mk 2 y y y 52B/1 1/80 STC - was 1/766 (cost reduced)
  Mk 3 y y y 52A/2 10/78 GEC - was 2/766
  Mk 4 y y y 52A/3 1/79 PYE - was 3/766
  Mk 5 y y y 52C/1 8/79 STC - was 4/766
  Mk 6 y y y 52B/2 2/81 GEC
  Mk 7 y y y 52B/3   PYE/TMC
  Mk 8 y y y 52A/4   PLESSEY
  Mk 9 y y y 52A/5   BTF
Tele 8786 Mk 1 y y y 7A   GEC
  Mk 2 y y y 54A/1   STC
  Mk 3 y y y 54A/4   PTL
  Mk 4 y y y 12A   PYE-TMC
  Mk 5 y y y 54A/1   GEC
  Mk 6 y y y 54A/3   TMC
Tele 8786RR Mk 1 y y y 7A   GEC
  Mk 2 y y y 54A/1   STC
  Mk 3 y y y 54A/4   PTL
  Mk 4 y y y 12A   PYE-TMC
  Mk 5 y y y 54A/1   GEC
  Mk 6 y y y 54A/3   TMC

How to wire your Telephone No. 786 to make it work on Plug and Socket

 

 
 
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Last revised: May 23, 2022

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