ATM SWITCHBOARDS T.267 - T.273

Ironclad Cordless Telephone Switchboards robustly constructed for use underground in conjunction with magneto mine telephones of the certified type. Strong cast-iron case fitted with hinged lid on which are mounted the various working components, keys, etc., making for accessibility. Connections are made by means of keys, and there are no cords or flexible connections to wear or break. Conversations can be continued whilst the board is under examination. The indicator drop shutters are fitted with contacts for ringing extension bells and are mechanically reset by an external knob.

These switchboards can be supplied with any number of ways and fitted with one, two or four through positions, enabling a corresponding number of conversations to take place simultaneously.

Model number and capacity
T.268 3 lines 1 through position fitted. L10in, W9.8in, D7in.
T.269 4 lines 2 through positions fitted. L13in, W9.8in, D7in.
T.267 6 lines 2 through positions fitted. L15.5in, W10in, D7in.
T.270 10 lines 4 through positions fitted. L21.5in, W15.8in, D7in.
T.271 12 lines 4 through positions fitted. L24in, W15.8in, D7in.
T.272 20 lines 4 through positions fitted. L30.5in, W22in, D7in.
T.273 30 lines 4 through positions fitted. L30.5in, W33.3in, D7in.

Taken from the A.T.M. Mine Telephones and Signalling Equipment Book - April 1939

MINE TELEPHONES AND SIGNALLING APPARATUS
A.T.M. FLAME-PROOF CORDLESS MINE SWITCHBOARDS

T.267. Six way
Robust design for use underground in conjunction with magneto mine telephones.
Strong flame-proof cast-iron case with hinged front, on which are mounted the various components, keys, etc., making for accessibility.
The drop-shutter indicators are disposed behind a strong plate-glass window, and are replaceable by an external restoring knob. They are fitted with local contacts for actuating a local alarm or extension bell.
Connections are made by means of keys, and there are no cords or flexible connections to wear or break.
Fitted with armoured cable glands if required.
Can be supplied for any capacity up to 25 lines and are equipped with either two or four through positions, enabling a corresponding number of conversations to take place simultaneously.

Finish: Grey enamel.
OVERALL DIMENSIONS:
Length, 1ft. 6ins. height, l2ins. depth, 7ins.
Weight, 54 lbs.

Taken from the ATM Mine Telephones and Signalling Apparatus Catalogue 1928

Last revised: October 06, 2012