Wall telephone, with integral bell, that's very much like the Siemens Brothers 366.  Bakelite cased with standard GPO style circuitry.  Generally fitted with an ATM Dial No. 24.

Used mainly in the UK on Private Automatic internal systems.

The Model L11186A2 was possibly used by the Hull Corporation Telephone department.  It also used a stainless steel dial finger plate.

When opening the case, release the two screws on the front cover and then pull them towards you are far as they will go.  They will not come out completely but if you do not pull them towards you then they will catch on the casing as the cover is swung open.  When closing the case it is also important to ensure the screws are pulled out.


Front view Internal view - with case hinged to left

Wiring a new style BT cord to a phone with diagram L530315A or L523602

  1. Remove the wire strap between terminal's 1 and E in the Bellset and replace with a 3.3k resistor .
  2. White of the line cord connects to terminal 1 of the Bellset.
  3. Red of the line cord connects to terminal 4 of the Bellset.
  4. Blue of the line cord connects to terminal 3 of the Bellset.
  5. Green of the line cord connects to terminal 2 of the Bellset.
  6. Disconnect the blue wire from the capacitor.

Additional Pictures

Earlier model shown above - identifiable by the square capacitor
(The dial cord shown is a modern plastic variant)


Straight from the skip - thanks to Dave Dockerill for the pictures
This telephone is fitted with fitted with an ATM Dial No. 24 - identifiable as the finger stop is not next to the digit 0.

Case open


This is a bellset that is marked Siemens and is connected to a case with Circuit Diagram L530315A



Circuit Diagram L532602
For both Telephone L1186B9 and L11186A9

Circuit Diagram L530315A
The Telephone is ATM, whilst the Bellset is Siemens

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Last revised: February 10, 2023