Universal Digital Patch Panel,Programs

TM 11-5895-1012-10

send with timing from an external

standard to both sending and receiving devices.

(5) The patch panel also incorporates a special

circuits utilizing either an external

function for

timing standard or timing from a receiving device to a

sending device. When a transmitted signal is to be

M3 to M2

receiving portion of the same

patched back

D3 to E2

purposes, a problem would nor-

equipment for

M3 to J3

mally arise. Since external timing is necessarily intro-

H3 to E1

duced on the line side of a jack field, a line-send-to-line-

L1 to J1

l (back to back) patch required to perform

F2 to F3

ve test for equipment external to the TCF con-

H3 to N3 (Not shown)

two timing signals (one injected into the send

Al to H1 (Not shown)

field and one received on the incoming line). Con-

A2 to M1 (Not shown

versely, an equipment send-to-equipment-receive (back

E3 to K1 (Not shown)

to back equip) patch required to perform the test for

H3 to N3 (Not shown)

equipment internal to the TCF contains no timing sig-

C3 to D1 (Not shown)

nal. When timing is sent from a receiving device to a

C3 to K3 (Not shown)

the same problem can occur (i.e., two

on a back to hack line and none on a

(2) When a patch cord plug is inserted into the

LINE jack, the following connections are made.

uip).

A push button "back-to-back" switch allows the remov-

Terminal

al of one of the two timing signals present in a back to

line patch and the introduction of timing in a

to-back equip patch. An indicator light as well as

switch position indicates the activation of this func-

External timing

tion in all cases.

(3) When a patch cord plug is inserted into the

(6) The signal common "ring" lead of an interrupt-

EQUIP jack, the following connections are made.

ed signal is never left open. It may be supplied DC

Terminal

ground or another program elected termination.

External timing

3-15. Universal Digital Patch Panel,

To plugged line equipment

Programs

To plugged line equipment

c. Black Receive Circuit, Program Module GP-5

(fig. FO-16).

(1) This programming module connects the fol-

lowing terminals:

B2 to E1

B1 to J3

C1 to F3

B3 to J1

C2 to N2

D2 to K3

3-12