Selector Test Jack pin out

Selector Test Jack. (text from page 115 of Atkinson)

Pinouts

13 14 L1 L2

7 8 9 10 11 12

1 2 3 4 5 6

The test jack of the 2000 type selector is of moulded bakelite and is designed on the unit principle to meet various circuit requirements. The top unit accommodates the selector lamp and the label, and provides a "parking place" for a U-link. The remainder of the test jack is built up of 6-spring units which are assembled to form a test jack of 12, All test jacks are numbered in a standard way, i.e. from left to right and upwards. For ease of maintenance the test jack springs are, as far as possible, arranged in the circuit in a uniform way. The springs on a 12-point test jack (by far the most common) are, for example, usually allocated as follows :
1. Rotary magnet.
2. Private (or test and guard) wire.

3, 4. First speaking pair.

5, 6. Second speaking pair.

7. Earth.8. Private wire.

9, 10. Test bell circuit (on 200-outlet switches).

11, 12. Rotary release drive circuit.

13, 14. U-link parking place (on lamp and label strip).

A red capped U-link is normally kept in the parking place where it is not connected to the circuit. A selector can be busied by removing this link to jack springs 7-8 and so connecting earth to the test (P) wire.

This link may also be momentarily inserted in springs 9 and 10 of 200-point selectors to determine whether an odd or even outlet has been seized. The short circuiting of 9&10 allows the test trunk bell to operate (via U connector 13) if the call is switched to the upper bank.
A green headed link is permanently held in springs 11 and 12 where it completes the drive circuit for the rotary magnet on release. If, for test purposes, it is desired to prevent the release of a switch, this link is temporarily withdrawn.

Connect a phone and rotarty release supply as follows