GEC K8100

K 8100
MAGNETO CALL MINING TELEPHONE

(CERTIFIED BY H.M. MINES DEPARTMENT)
FLAMEPROOF AND INTRINSICALLY SAFE

Specially designed to meet mining requirements and to comply with H.M. Home Office Regulations. The cast-iron case is strong and well finished, particular care being taken to make the joint between the case and lid flameproof as well as watertight. Specially designed to meet mining requirements The flanges are one inch in width and machined so as to cool effectively any hot gases escaping as as the result of an internal explosion. The cover is securely bolted to the case. The internal unoccupied space is kept down to a minimum so as to limit the amount of explosive gas which might accumulate.

The equipment comprises:

Powerful Generator, with canvas drive, and fitted with strong handle working through a flameproof and watertight gland.

Polarised Ringing Movement wound to a resistance of 1,600 ohms and fitted with 6-inch gong. The bobbins are wound with enamelled wire.

Solid Back Long Distance Transmitter fitted in an iron chamber on the front of door, the diaphragm being protected from damage by a fine-meshed brass gauze. An induction coil wound with enamelled wire is fitted inside the case.

Double Pole Bell Receiver. This receiver is fitted inside the case and is arranged so as to revolve when the listening tube (which is fitted on the left-hand side) is lifted to the ear.. At the diaphragm end of the receiver a cam is fitted. This revolves with the receiver and at the same time operates the switch springs controlling the speaking battery and receiver circuits. The gland through which the tube passes is flameproof and watertight.

Two No. 2 G.E.C. Dry Cells are fitted in metal containers which are mounted on the inside of the door by means of a metal band.

Attached to the bottom of the case is a chamber which contains strong and well designed line terminals.

Four lugs are fitted on the sides and back of the instrument for fixing.

Weight. 80 lbs.

Dimensions. 19.25 x 14.25 x 10.75 ins

Cost in 1916 was £10.0.0
Cost in 1935 was £18.18.0

Also called the TEL/11/MWU

Last revised: 09 July, 2007