Notes For All Schematics And Circuit Boards - Motorola CM Series Service, Maintainability

Notes For All Schematics and Circuit Boards

5.0 Notes For All Schematics and Circuit Boards
* Component is frequency sensitive. Refer to the Electrical Parts List for value and usage.
1. Unless otherwise stated, resistances are in Ohms (k = 1000), and capacitances are in picofarads
(pF) or microfarads (µF).
2. DC voltages are measured from point indicated to chassis ground using a Motorola DC
multimeter or equivalent. Transmitter measurements should be made with a 1.2 µH choke in
series with the voltage probe to prevent circuit loading.
3. Interconnect Tie Point Legend:
Signal Name
16_8MHz
3V
5V
5V_CH
9V
9R
ASFIC_CS
B+
BATT_SENSE
BOOT_EN_IN_CH
BW_SEL
CH_ACT
COMM_DATA_SEL_CH
D3_V3
DEMOD
DETECTOR_AUDIO_SEND_BRD
DISPLAY_CS_CH
EMERGENCY_ACCES_CONN
EMERGENCY_SENSE
EXTERNAL_MIC_AUDIO ACCES_CONN
F1200
FILT_SW_B+
FLAT_TX_AUDIO_INPUT_ACCESS_CONN
HANDSE RX_AUDIO_CH
HOOK_CH
HSIO
IGNITION
KEYPAD_COL_CH
LOC_DIST
LSIO
MIC_AUDIO_CH
Signal Description
16.8MHz Reference Frequency from Synthesizer to ASFIC
3V RF regulator
5V RF regulator
Optional 5V for Control Head
Regulated 9.3V Supply Voltage
9V to enable RX_INJ when RX_EN is active
ASFIC Chip Select
13.8V Supply Voltage
Battery Voltage Sense Line
Boot Mode Select
Select BW (12.5 KHz, 25 KHz)
Channel Activity Indicator Signal (Fast Squelch)
Display Driver Command/ Data Select
Regulated 3.3V supply voltage for Voice Storage
Audio Output Signal from the Receiver IC
Flat Audio to Option Board
Control Head Chip Select
Emergency line to switch on the radio voltage regulators
Emergency sense to µP
External (from accessory connector) microphone input
Interrupt line from ASFIC CMP
Switched 13.8 V supply voltage
Flat TX input from accessory connector
Handset Audio Output
Hang-up switch input
High Speed Clock In / Data Out
Ignition Line to switch on he radio's voltage regulator
Keypad Matrix Column
Enable Attenuator for RX line
Low Speed Clock In / Data Out
Microphone Input
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