Section 9 conventional channel module (ccm), 1 description, 1 repeater signaling – EFJohnson 3000 SERIES User Manual

Page 85: 2 repeater control, 3 voice connection, 4 internal communication, 2 ccm setup procedure, 1 ccm switch settings, 2 afsk communication on the main lines, 3 ccm jumper placement

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9-9

CONVENTIONAL CHANNEL MODULE (CCM)

SECTION 9 CONVENTIONAL CHANNEL MODULE (CCM)

9.1 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 7-1
for the Basic Board block diagram. The Conventional
Channel Module (CCM) connects the Switch to a
Conventional Repeater. Each repeater has a CCM that
controls the repeater through logic signaling.

9.1.1 REPEATER SIGNALING

The CCM exchanges control information with

the CRM via Audio Frequency Shift Keying (AFSK)
data in a blank and burst mode on the voice audio
path.

9.1.2 REPEATER CONTROL

The CCM monitors and controls the repeater

transmit, receives confirmation of all requests made to
the repeater and sends information the repeater
received.

9.1.3 VOICE CONNECTION

The CCM provides a 4-Wire 600 ohm balanced

voice connection to the repeater, converts audio to and
from Pulse Code Modulation (PCM), transmits and
receives on the PCM buses, and controls voice audio
gating to and from the repeater.

9.1.4 INTERNAL COMMUNICATION

The CCM uses the Intra-Terminal Data Bus

(IDB) to communicate to other modules and send
messages to and receive messages from the Call
Processor that controls its actions.

The status of the CCM/CRM/Repeater combina-

tion is determined by the other modules by what the
CCM transmits on the Channel Status Bus (CSB).
The other modules monitor the CSB and determine if
a CCM has the appropriate group and status for the
type of communication the module requires.

9.2 CCM SETUP PROCEDURE

9.2.1 CCM SWITCH SETTINGS

Refer to Figure 9-1 for Alignment Points

Diagram.

Command and Control Communication

The command and control communication to the

Conventional Repeater Module (CRM) is by blank
and burst mode of Audio Frequency Shift Keyed data
on the Main audio lines.

9.2.2 AFSK COMMUNICATION ON THE MAIN

LINES

Refer to Table 9-1 for switch settings.

9.2.3 CCM JUMPER PLACEMENT

Table 9-1 CCM SWITCH SETTINGS

Switch

Open Sections

Close Sections

S1
S3
S4
S5

1
1
1

-

-

2
2

-

-

3
3

-

4
4
4

-

-
-
-

1

2

-
-

2

3

-
-

3

-
-
-

4

Table 9-2 CCM JUMPER PLACEMENT

JU

Pin

Description

J24

1 to 2*
2 to 3

Selects 27512 EPROM operation
Selects 27256 EPROM operation

J27

1 to 2
2 to 3*

Not used
Normal operation

P33

1 to 2
3 to 4
5 and 6

open
open
open

J36

1 only
1 to 2
2 to 3

Not used
-48V E-lead operation
-15V E-lead operation

J14
J15
J21
J22

Jumper pin 1 to 2 for high impedance ground path
for split 600 ohm inputs and outputs. Leave open if
no ground path desired.

* Indicates normal operation.

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