Number 3 Type Toll Switchboard (with calculagraph)


ABBOTT | Teléfono
Personaje: ABBOTT, Henry.

When the operator touched the tip of the cord to the jack of a manual line, the click was heard in the operator's headset. The outgoing "OGT" jacks marked "Casey Dial" are connected to selectors in the same rank as the local first selectors so 7-digit dialing is necessary. The jacks to route "015 OGT to all NPA" are connected to non digit-absorbing selectors that cut through on only one digit reach a 486 number the routing is 6+4D or 6 plus the last four digits of the called number.

The Calculagraph is a motor driven timer that stamps the elapsed time on two dials showing minutes and seconds duration of the call. Another impression shows the TOD (Time Of Day). Manual toll tickets required an army of clerks to rate and calculate the charge for the call and post the charge to the customer bill. The Calculagraph also printed the serial number of the individual unit so there was no question if the call start and end was imprinted by the same timer. Green handle forward printed the TOD and serial number. Green handle back printed the clock circles and was done when the call began. Red handle back printed the clock hands and the serial number again and was done when the call ended.

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