DISPATCH INTERFACE MODULE (DIM)

SECTION 11 DISPATCH INTERFACE MODULE (DIM)
11.1 DESCRIPTION

Refer to 3000 Series Switch Service Information manual, Part No. 001-3139-102, for the component layout, parts list and schematic. Refer to Figure 7-1for the Basic Board block diagram. The Dispatch Interface Module (DIM) uses one of two methods of interface to the dispatch equipment:

1.Direct Connection

2.Tone Remote

A DIM with direct connection is associated with only one group code and uses a form of Type II E&M lead input similar to the mobile PTT.

A DIM with tone remote connection decodes guard tone for the PTT indication and decodes DTMF to select from one of ten group codes. A control sequence uses the DTMF to place the DIM in scan mode or to stop and use a specific group code. The tone remote feature requires the use of a plug-in personality card.

The DIM connects the 4-Wire 600 ohm balanced audio with the Pulse Code Modulation (PCM) data paths and communicates to other modules via the Intra-Terminal Data Bus (IDB). The DIM also monitors the Channel Interface Module (CIM) Channel Status Bus (CSB) to determine if a CIM is active with a DIM group.

11.2 DIM SETUP PROCEDURE

11.2.1 SWITCH SETTINGS

Refer to Figure 11-1for Alignment Points Diagram.

Command and Control Communication

The command and control communication to the Consoles may take the place by two different forms. The form chosen is typically dependent upon the type of console connected to the DIM.

1.If the Console is a normal contact closure PTT, the connection is by direct connect. This uses the E&M lead input and output.

2.A Tone Remote Console uses 4-Wire audio for the connection. The DIM requires the use of a tone remote personality card.

Table 11-1 DIM SWITCH SETTINGS

Switch

Open Sections

 

Close Sections

 

 

 

 

 

 

 

 

 

 

Direct Connection

 

 

 

 

 

 

 

 

 

 

 

 

S1

1

2

-

4

-

-

3

-

S3

1

2

3

4

-

-

-

-

S4

1

2

3

4

-

-

-

-

S5

-

-

-

-

1

2

3

4

 

 

 

Tone Remote

 

 

 

 

 

 

 

 

 

 

 

 

 

S1

1

2

3

4

-

-

-

-

S3

1

2

3

4

-

-

-

-

S4

1

2

3

4

-

-

-

-

S5

-

-

-

-

1

2

3

4

11.2.2DIM JUMPER PLACEMENT

Table 11-2 DIM BOARD JUMPER

PLACEMENT

JU

Pin

Description

 

 

 

J24

1 to 2*

Selects 27512 EPROM operation

 

2 to 3

Selects 27256 EPROM operation

J27

1 to 2

Not Used

 

2 to 3*

Normal Operation

P33

1 to 2*

No personality card attached

 

3 to 4*

No personality card attached

 

5

open

 

6

open

J36

1 only*

Not used

 

1 to 2

-48V E-lead operation

 

2 to 3

-15V E-lead operation

J14

Jumper pin 1 to 2 for high impedance ground path

J15

for split 600 ohm inputs and outputs. Leave open if

J21

no ground path desired.

J22

 

 

*Setting for Normal operation.

11-1