GENERATORS


Generators can be indentified by numbers with one or two suffix letters.  The first letter will signify the resistance (A to L used), whilst the additional suffix letter (N to Z) will signify that the generator is mounted in some way.

The resistance letters are:-
A = 500 ohms
B = 450 ohms
C = 400 ohms
D = 300 ohms
E = 200 ohms
F = 110 ohms
G = 60 ohms

Refer to Diagram for explanation of the Connection Code - Diagram T. L. 707. or N 1200.

 
Generator No. 2A

Generator of 200 ohms with three magnets.
Connection code K.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Handle, Generator, No. 9.

Superseded by No. 8A.

 

 
Generator No. 2AN

Wall mounted generator.
Connection code K.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Generator No. 2A.

 

 
Generator No. 3A

Generator of 200 ohms with four magnets.
Connection code L.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Handle, Generator, No. 4.

Superseded by No. 8A.
 

 
Generator No. 3AN

For table or wall fixing.
Mark 234 includes a Generator 3A.
Connection code L (Mark 234)
Connection code F (Mark 2013A)
Connection code B (Mark N.T.9)
Connection code E (Mark GNH)
Diagram T. L. 707. or N 1200.

Superseded by No. 8AN.
 

 
Generator No. 4C

2 magnet (type 234 and 235) or three magnet (mark 236).
Coil resistance is 400 ohms.
Connection code K.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Handles, Generator, No. 6.

 


 
Generator No. 4CN

Table or wall fixing generator.
Connection code K.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Generator No. 4C.

Generator No. 4CO

For use on Telephone, No. 59 (mark N.T. 8)

 

 
Generator No. 4CP

For extension stations on circuits connected at the main station to Bellset, No. 20.  For table or wall fixing.
For connections see Diagram N 1597.
Includes:-
1 x Condenser, M.C., No. 1 or No. 102.
 

 
Generator No. 5E

Generator of 200 ohms with four magnets.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Handle, Generator, No. 12.

 

 
Generator No. 5EN

Wall mounted generator.
Connection code O.
Diagram T. L. 707.
Includes:-
1 x Generator, No. 5E.

 

 
Generator No. 8A

Generator of 500 ohms with four magnets.
Connection code K.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Handle, Generator, No. 16 (mark 2010).
1 x Handle, Generator, No. 13 (mark 234).

Supersedes No's 2A, 3A and 20A.


 
Generator No. 8AN

For table or wall fixing.
Connection code K.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Generator, No. 8A.
1 x Handle, Generator, No. 7.

Supersedes Nos. 2AN, 3AN and 20AN.
 

 
Generator No. 10G

Generator of 60 ohms with nine magnets.
Connection code O.
Diagram T. L. 707. or N 1200.

 

 
Generator No. 11A

Generator of 60 ohms with nine magnets.
Connection code O.
Diagram T. L. 707. or N 1200.
Includes:-
1 x double pulley.

 

 
Generator No. 11AN

Generator with "Busy back gear".
Includes:-
1 x Generator, No. 11A.

 

 
Generator No. 12A

Generator of 500 ohms with four magnets.
Connection code P.
Diagram T. L. 707. or N 1200.

 

 
Generator No. 12AN

Generator with Wall fixing.
Connection code P.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Generator, No. 12A.
 

 
Generator No. 13F

Generator of 110 ohms with five magnets. Connection code K.
Diagram T. L. 707. or N 1200.
 

 
Generator No. 13FN

Generator wall fixing.
Connection code K.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Generator, No. 13F.
1 x Handle, Generator, No. 19.
 

 
Generator No. 15

Generator of 500 ohms with four magnets.
Diagram T. L. 707. or N 1200.
Used on switchboards.

Superseded by Generator No. 26....

 

 
Generator No. 20A

Generator of 500 ohms with four magnets.
Connection code D or F.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Handles, Generator, No. 13.
1 x Handles, Generator, No. 16 (mark 2013)

 

 
Generator No. 20AN

Table or wall fixing.
Connection code D.
Diagram T. L. 707. or N 1200.
Includes:-
1 x Generator, No. 20A.

Superseded by No. 8AN.

 

 
Generator No. 23A

Generator of 500 ohms with four magnets.
Connection code C.
Diagram T. L. 707. or N 1200.

 

 
Generator No. 24A

Generator of 500 ohms with four magnets.
Connection code M.
Diagram T. L. 707. or N 1200.

 

 
Generator No. 26A

Generator of 500 ohms with one magnet (Alnico).
Connection code K.
Diagram T. L. 707. or N 1200.
In general use from the 1930's onwards.

 


 
Generator No. 26AN

Generator for table or wall fixing.
Includes:-
1 x Generator, No. 26A.
1 x Handle, Generator, No. 20.
 

 
Generator No. 26AP

For extension stations on long circuits connected at the main station to Bellset, No. 20 when Generator No. 4CP is not powerful enough.  For table or wall fixing.
Includes:-
1 x Condenser, M.C., No. 102.
1 x Clip, No. 14.
1 x Generator, No. 26.
1 x Handle, Generator, No. 20.
 

 
Generator No. 28HN

For table or wall fixing.
Includes:-
1 x Case No. 54.
1 x Handle, Generator, No. 19.
1 x Generator No. 28H.
 

 

 

 
 
BACK Home page BT/GPO Telephones Search the Site Glossary of Telecom Terminology Quick Find All Telephone Systems

Last revised: September 28, 2019

FM