Mining Switchboard

Type Certified by The Mines Department, Certificate No. T/Tel/25, as intrinsically safe. For Surface Use only

Cordless Telephone Switchboards constructed in wood for surface use only in conjunction with Magneto Mines Telephones of the certified type. Hinged front on which are mounted the indicators, keys, etc. There are no cords or flexible connections to break, and conversations can be continued whilst the board is under examination. The indicator drop shutters are fitted with contacts for ringing extension bells and are hand restored. An alarm bell and key are also fitted. These switchboards can be supplied with any number of ways and with one, two or four through positions, enabling a corresponding number of conversations to take place simultaneously.

Model number and capacity
T.293 3 lines 1 through position fitted L14.5in, W12.5in, D5.5in.
T.294 4 lines 2 through positions fitted L17.75in, H12in, D5.5in.
T.295 6 lines 2 through positions fitted L20in, W12-in. D5.5in.
T.296 10 lines 4 through positions fitted L24in, W18.5in, D5.5in.
T.297 12 lines 4 through positions fitted L26.8, W18.5in, D5.5in.
T.298 20 lines 4 through positions fitted L24.5in, W31.8in, D5.8in.
T.299 30 lines 4 through positions fitted L31.5in, W32in, D5.8in.

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

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Last revised: October 06, 2012