Adaptors, Local Battery

These adaptors were for use in a telephone connected to a local battery system.  They were introduced at the same time as the 706, 710 and 711 type telephone, because these were standard telephones and did not have many variations like the earlier models.  At this point in time L.B. telephone use was dramatically reduced, so installing an optional adaptor was a cost effective way of supplying an L.B. telephone.  When an adaptor was fitted the telephone regulator would be inverted to disable the onboard active components and also short together three circuit board contact points.

All are fitted with an Inductors, Coil No. 153A or 153B.  The No. 153B is not as high as the No. 153A.  Direct current resistance is 15ohms.  The winding is 470 turns of 0.0068" diameter enamelled wire (37 swg).

Specification - D2108A.

Adaptor, Local Battery No. 1
A metal bracket fitted with an Inductor, Coil No. 153A and a springset comprising of a 1 x M contact set.

These were used in the Telephone No. 706.

Introduced in 1960.

Superseded by the Adaptor, Local Battery No. 5.

Made by Ericsson, their part N23232A1.

Drawing - 91364.

These Adaptors are fitted in a similar way to the auxiliary gravity-switch spring-sets.

These were used in the Telephone No. 706.

Introduced in 1960.

Superseded by the Adaptor, Local Battery No. 6.

Made by Ericsson, their part N23233A1.

Drawing - 91365.

Adaptor, Local Battery No. 4
A metal bracket fitted with an Inductor, Coil No. 153A and a springset comprising of a 1 x M contact set.

These Adaptors are fitted in a similar way to the auxiliary gravity-switch spring-sets.

Used in the Telephone No. 710.

Introduced in 1962.

Made by Ericsson, their part N23611A1.

Drawing No. 91358.

Adaptor, Local Battery No. 4

These Adaptors are fitted in a similar way to the auxiliary gravity-switch spring-sets.

Used in the Telephone No. 706.

Introduced in 1962.

Drawing No. 91636.

These were used in the Telephone No. 706.

Introduced in 1962.

These Adaptors are fitted in a similar way to the auxiliary gravity-switch spring-sets.

Diagram - N808.

Drawing - 91637.

Adaptor, Local battery No. 6

These were used in the Telephone No. 711 on CBS No. 2 & 3 systems and generator ringing circuits..

Introduced in 1964.

Made by GEC.

Diagrams - N811 and N848.

Drawing - 91894.

These were used in the Telephone No. 711.

Introduced in 1964

Made by GEC.

Drawing - 92126.

Last revised: August 16, 2026