Controller Circuits
1-11
3.4
Keypad
The keypad block diagram is shown at Figure 1-2. Pressing a key creates two distinct voltages,
KEYPAD_ROW and KEYPAD_COL. These voltages are routed to the microprocessor on the main
board. The microprocessor samples the voltages to determine which key has been pressed.
Figure 1-2
Keypad Block Diagram
3.5
Speaker and Microphone Assemblies
The speaker and microphone are mounted in the radio front housing. They are connected to the
audio circuits on the main board, the speaker via connector J491 pins 1 & 2 and the microphone via
connector J470 pins 1 & 2. Refer to the Audio Circuitry schematic diagram for details.
3.6
LCD Display Module
The display module is part of the keypad and is connected to the keypad board via a flex cable to
connector J1 on the keypad board.
Keypad
Button
MCP
Keypad Row
Keypad Row
Keypad Row
Keypad Column
Keypad Column
Keypad Column
28 Pin Connector
(k
e
ypad Board)
28 Pin Connector
(Main Board)
Summary of Contents for CP 140
Page 1: ...Commercial Series CP140 CP160 CP180 Portable Radios Detailed Service Manual 6866550D20 O ...
Page 2: ...ii ...
Page 4: ...iv ...
Page 12: ...viii ...
Page 28: ...iv ...
Page 40: ...1 12 THEORY OF OPERATION ...
Page 48: ...2 8 TROUBLESHOOTING TABLES ...
Page 50: ...3 2 CONTROLLER KEYPAD SCHEMATICS ...
Page 58: ...3 10 Keypad Board Parts List 8466565A01 O ...
Page 62: ...iv ...
Page 66: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 90: ...3 16 TROUBLESHOOTING TABLES ...
Page 92: ...4 2 VHF PCB SCHEMATICS PARTS LISTS ...
Page 108: ...iv ...
Page 112: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 136: ...3 16 TROUBLESHOOTING TABLES ...
Page 138: ...4 2 UHF1 PCB SCHEMATICS PARTS LISTS ...
Page 154: ...iv ...
Page 158: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 182: ...3 16 TROUBLESHOOTING TABLES ...
Page 184: ...4 2 UHF2 PCB SCHEMATICS PARTS LISTS ...
Page 200: ...iv ...
Page 204: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 228: ...3 16 TROUBLESHOOTING TABLES ...