. The telephone system of the British post office. A practical handbook . FiGUiSE 128. The general appearance of the switch-board and a sectional drawingare shewn in Figujre 128. Each subscribers line terminates upon a switch-spring and an indicator. The switch-springs are acommodated at the top Indicators and Switch-Springs. i6i of the board, and it will be observed that there are six rows of ten extra switch-springs are provided for various junction circuits,should they be necessary. Similarly the five indicators below the fiftysubscribers indicators are provided for similar purpos
. The telephone system of the British post office. A practical handbook . FiGUiSE 128. The general appearance of the switch-board and a sectional drawingare shewn in Figujre 128. Each subscribers line terminates upon a switch-spring and an indicator. The switch-springs are acommodated at the top Indicators and Switch-Springs. i6i of the board, and it will be observed that there are six rows of ten extra switch-springs are provided for various junction circuits,should they be necessary. Similarly the five indicators below the fiftysubscribers indicators are provided for similar purposes. The pairs ofcords are placed upon a, small shelf above the indicators and below theswitch-springs, the object being to avoid the cords crossing in front ofand thus obscuring the view of the indicators. The last row of tenindicators are for the ring-off signals, and upon the shelf below theseindicators are placed the ringing and speaking keys. The subscribers hnes terminate upon five-point switch-springs, the innersprings of which are connected to low resistance (lo
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Keywords: ., bookcentury1900, bookdecade1900, booksubjecttelepho, bookyear1901
