TRAFFIC CONTROL TELEPHONE SYSTEMS Circuit - Sam Hallas

One No. 4002-B Selector Key Case (capacity twenty Selector Keys) for each
additional twenty or fraction of twenty keys.
One No. 4001-A Selector Key for each No 4301-A or 4304-A Selector installed
at Way Stations.
One No. 4001-A Selector Key for "General Call."
One No. 4001-A Selector Key for " Time Sending."
One No. 4001-C Selector Key Space for each position in items 2 and 2a not
fitted with a key.
Two No. 4110 Type Protectors.
One No. 4001-A Selector Time Sending Set.
One No. 4086-A Telephone Set.
One No. 4002-A Jack Box.
Three No. 4403-AA or 4405-C Telephone Sets.
One No. 4001-A Foot Switch.
One No. 4001-A or 4001-B Foot Switch Attachment (if required).
One Storage Battery (4 volts) for Controller's Telephone.
One Storage Battery (10 to 12 volts) for control and impulsing relays.
Main signalling supply voltage to be in accordance with curves on pages 51 and
52 derived from A.C. mains rectifier, storage battery and charger or primary
cell battery, as required.
One 4001-B Selector Test Set (if required).
NOTE.-For each way station equipped with a No. 4305-B Selector, the 4001-A
Selector Key specified under Item 3 is to be replaced by a No. 4001-B Selector
Key. One 4001-B Selector Key is also required for each additional extension
bell connected to the 4305-B Selector.
At Each Way Station
Wall Mounted Telephone
One No. 4001-A Selector Set and
One No. 4308-C Telephone Set, or
One No. 4002-A Selector Set.
(Combined Telephone and Selector Set.)
Desk Telephone Set
One 4001-A Selector Set.
One 4311-A Telephone Set.
One 4001-A Foot Switch.
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