Service Manual

MM-E 2072-09333-00
2-11
LCD
LORD
P501
J6
GPS
GPS
Receiver
J8
Backup
Battery
J4
HI POWER
J3
J1
P3
RX
P2
J2
TX
P4
J5
ACCESSORYANTVDC IN
E2
E1
J3
P2
P4
P6
Body AssemblyControl Head
Interconnection
Cable
INTERCONNECTION
P1P2
J4
Socket
for SD
Memory
Card
Speaker
Microphone
Figure 2-9. Micom-Z Trunk-Mount Wiring Diagram
2-1.2.3 Functional Block Diagram
The functional block diagram of Micom-Z trunk-mount version is shown in Figure 2-10.
2-1.2.3.1 Transmit Path
a. Selection of Signal Source. The transmit path can receive modulation signals from a
microphone connected to the audio connector of the control head, or signals from equipment
connected to the rear panel ACCESSORY connector (audio from an accessory device, a
modem, or telegraphy). Each source provides a different PTT signal, and therefore the selection
of the signal to be transmitted is made in accordance with the active PTT signal:
• MIC PTT – PTT from the microphone connected to the control head connector, transmits the
voice signal provided by the microphone. The microphone signal passes through a buffer,
which converts the signal to a balanced signal, for transmission to the body assembly through
the interconnection cable. Another buffer located on the INTERCONNECTION module
converts the balanced signal to a single-ended signal, which is supplied to the audio amplifier.
The PTT signal also passes through an RS-485 line driver, for transmission to the body
assembly through the interconnection cable. An RS-485 line receiver located on the
INTERCONNECTION module converts the balanced RS-485 signal to the internal logic
levels.