Electrostatic Transient Protection; Jumper Functions - Motorola GM-950 Manual

Radio
J0101
1
2
13
4
10
11
17
18
8
6
5
7
16
3
12
3.13

Electrostatic Transient Protection

Electrostatic transient protection is provided for the sensitive components in the HHCM by diodes
VR0901, VR0921, VR0922, VR0924 - VR0929. The diodes limit any transient voltages to tolerable
levels. The associated capacitors provide Radio Frequency Interference (RFI) protection.
3.14

Jumper Functions

The jumpers are used to adapt the function of the keypad buttons for different keypads.
Introduction/Theory of Operation
Adapter PCB
J0950 P0951
18 18
17 17
6 16
15 15
9 9
8 8
2 4
1 1
11 14
13 13
14 3
12 12
3 10
16 6
7 7
Cable HHCM
Connector J0951
1 12
2 10
3 2
4 3
10 13
11 11
15 8
18 14
5 5
6 6
16 15
7 1
9 4
13 9
12 7
Theory of Operation
Description
INT SPKR+
INT SPKR-
ANALOG 3
PTT
ANALOG 1
ANALOG 2
FLT A+
ON OFF CONTROL
LCD CLCK BUF
SPI DATA BUF
LED CLCK BUF
GND
MIC
HOOK
LED CE
4C.1-5