Motorola EP350 Service Manual page 48

7-2
6. Reference Designators are assigned in the following manner:
7. Circuit Block Interconnection Legend:
+5V
+3.3V
SWB+
BAT+
+10V
RESET
TX_EN1
TX_EN2
TXVB
TX_AF3
TX_SUB_TONE
RX_B+
RSSI
Busy
FTV
RX_AF1
PLL_LD
N/S SW
1/2VCC
Ref. No. Series
101 – 199
1001 – 1099
201 – 299
301 – 399
401– 499
501 – 599
601– 699
701– 799
Name
5 Volts (Regulated)
3.3 Volts (Regulated)
Switched Battery Voltage
Unswitched Battery voltage
Digital 10V(Regulated)
Low-line reset signal fromU107 to U101 Pin 10
Transmit enable signal from U101 Pin 84
Transmit enable signal from U101 Pin 85
TX operating voltage
TX audio signal from audio processor IC to TX Audio
filter
TX sub tone signal from audio processor IC to TX
modulation.
RX operating voltage
RX signal strength indication from IF IC to U101
RX detect signal from IF IC to U101
RX frequency shift voltage
RX audio signal from IF IC to Audio processor IC
PLL lock detect signal from PLL IC to U101
Channel space selectable Switch (12.5 kHz/25 kHz)
1.9 volts (divided by U502-D)
UHF2 Schematic Diagrams, Overlays, and Parts Lists: Introduction
Circuit Block
Microprocessor & audio control
circuits
Microprocessor & audio control
circuits
IF IC circuit
Front-end and 1st Mixer
Transmit RF stage & Auto power
control
Base band & generating circuit
Audio amplifier
VCO & PLL Synthesizer
Description