Universal Digital Patch Panel, Programs

TM 11-5895-878-14&P

Below the connectors are 24 program modules. Between

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

the connectors and program boards there is a jack set ID

interrupted signal is never left open. It may be supplied

strip indicating the jack set associated with each program

DC ground or another program elected termination.

aboard.

b. Circuit Functions (fig. FO-7). Each jack set is

2-11. Universal Digital Patch Panel, Programs

connected (through a flexible printed circuit board) to a

a. General.

There are 17 different program

program board. The board is programmed by a program

modules provided to be used with the patch panel. The

module (containing jumpers) to set up an operation circuit.

modules are identified as PROGRAM MODULE

The functions that may be performed by the circuits are

ASSEMBLY LBAD-D-52724 GP-1 through GP-17. The

given in (1) through (6) below. The actual circuits for which

circuit configuration for each group is shown in figures 2-

modules are available are given in paragraph 2-11.

20 through 2-36. The in module jumpers and jack

(1) Provides a normal through path for digital

functions are given in b through r below. The function of

signals when no patches are made.

each group module is as follows:

(2) When patching in a replacement sending

Group No.

Function

device, the patching configuration will terminate the

Red Receive

interrupted sending equipment in an impedance equal to the

Red Send

input impedance of the receiving device.

Red Control

Black Send

(3) When patching in a replacement receiving

Black Receive

device the patching configuration will hold the interrupted

High Level Send

receiving equipment with a holding voltage or current equal

High Level Receive

to the mark voltage or current transmitted by the sending

Low Level Send W/Timing From External

device.

Standard To Both Sender & Data Receiver

(4) The patch panel will perform the above

9 Low Level Send W/Timing From Data Receiver

functions for all the following types of digital signals:

To Data Sender

(a) Low level 6 VDC send and receive.

10 Low Level Send W/Timing From Data Sender To

(b) Low level 3 VDC send and receive.

Data Receiver

11 Low Level Receive W/Timing (Always From Data

receive.

Sender To Data Receiver).

(d) Low level receive with associated

12 Low Level 6 VDC Send

timing.

13 Low Level VDC Receive

14 Low Level Balanced (+3V and -3V) Send.

(e) Low level send with timing from sending

15 Low Level Balanced (3V and -3V) Receive.

to receiving device.

16 Black Send (Modified - Less Station Clock)

(f) Low level send with timing from

17 Black/Red Receive

receiving to sending device.

NOTE

(g) Low level send with timing from an

For terminal identification figures 2-

external standard to both sending and receiving devices.

20 through 2-36, refer to figure FO-7.

(5) The patch panel also incorporates a special

b. Red Receive Circuit, Program Module GP-1 (fig.

function for those circuits utilizing either an external timing

2-20).

standard or timing from a receiving device to a sending

(1) This programming module connects the

device. When a transmitted signal is to be patched back to

following terminals:

the receiving portion of the same equipment for testing

B2 to E1

purposes, a problem would normally arise. Since external

B1 to J3

timing is necessarily introduced on the line side of a jack

C1 to F3

field, a line-send-to-line-receive (back to back line) patch

B3 to J1

required to perform the above test for equipment external to

D2 to K3

the TCF contains two timing signals (one injected into the

L1 to J1

send field and one received on the incoming line).

F2 to F3

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

M3 to J3

to back equip) patch required to perform the test for

H3 to El

equipment internal to the TCF contains no timing signal.

(2) When a patch cord plug is inserted into

When timing is sent from a receiving device to a sending

the LINE jack, the following connections are made.

device the same problem can occur (i.e., two timing signals

Terminal

Termination

on a back to back line and none on a back to back equip). A

To TCF plugged equipment

push button "back-to-back" switch allows the removal of one

To TCF plugged equipment

of the two timing signals present in a back to back line patch

Unterminated

and the introduction of timing in a back-to-back equip patch.

Unterminated

An indicator light as well as switch position indicates the

(3) When a patch cord plug is inserted into

activation of this function in all cases.

the EQUIP jack, the following connections are made.

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