Original model Interim model

Known as `The Corporation Set' (because many were supplied to Municipal systems) this is the GPO version of the National Telephone Companies NT 13 model.  The telephone was supplied with a magneto bell and generator and was used on C.B.S. and magneto circuits.

The GPO model had a wooden top whilst the steel body was printed with a wood grain finish.  Whereas the private models had transfers on the front of the case the GPO version had an instruction notice frame.

The later GPO variant (shown to the right) had a Tele No. 164 as a handset.  This was an interim modification as the original handset, Telephone No. 28, was a source of complaints about faint speech.  It was eventually decided to replace the whole set instead offering the customer the choice of a Telephone No. 4 or Telephone No. 11.  If the customer would pay the extra rental charge then they could opt for the Telephone No. 162.

Early table telephones were connected to the internal wiring with a Strip, Flexible Cord Connection.  Click here for more information.

See also the Telephone Efficiency Committees Report on Local Battery Area telephones.

Circuit Diagram - N188 (dated 1917).  The NTC version predates the diagram by at least 5 years.

Circuit Diagram - C.B.S. 232.

Made by British Ericsson.

Telephone includes (1928):-
1 x Cord, instrument, No. 604 or 606.
1 x Cord, Instrument, N.T. No. 56.
1 x Handle, generator, No. 17.
1 x Strip, flexible cord connection, 7-terminal.
1 x Telephone No. 28.

Marks I.S.T.J., I.S.T.K. and N.T. 8 include:-
1 x Block, 7-terminal.
1 x Cord, instrument, No. 606.

Mark I.S.T.J. include:-
1 x Jack, 4-way, special.
1 x Plug No. 406.

NTC version of this instrument


Telephone No. 88 Mark ISTJ with Telephone No. 164
Picture taken May 1931

Telephone No. 88 Mark NT 6 with Telephone No. 164
Picture taken May 1931

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Last revised: November 17, 2021