Analog Mode Of Operation; Figure 3-1. Apx 7000 Overall Block Diagram (Vocon Board Mncn6200); Figure 3-2. Apx 7000 Overall Block Diagram (Vocon Board Mncn6202) - Motorola APX 7000 Basic Service Manual

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Figure 3-1. APX 7000 Overall Block Diagram (VOCON Board MNCN6200)

Figure 3-2. APX 7000 Overall Block Diagram (VOCON Board MNCN6202)

3.2

Analog Mode of Operation

This section provides an overview of the analog mode receive and transmit theory of operation.
3.2.1 Receiving
The RF signal is received at the antenna and is routed through the Auxiliary and Multi Switch (SP3T)
ICs. The latter contains a switchable attenuator that is enabled at predetermined RF power
thresholds present at the antenna port. The output of the Multi-switch IC is applied to the first SPST
band select switch to select the either the VHF or 700,800 bands
bands (see Figure
and VHF or UHF2 bands
Antenna
40
Transceiver
Board
Antenna
40
Transceiver
Board
3-4), VHF/UHF1 bands
(see Figure
Basic Theory of Operation: Analog Mode of Operation
Expander
Board
60
VoCon
Board
60
Option
Board
Expander
Board
60
VoCon
Board
60
Option
Board
(see Figure 3-5), UHF2 or 700,800 bands
3-7).
14
External accessory connector
External antenna
40
Front display
60
Keypad
20
50 20
Top display
Controls top
30
14
External accessory connector
External antenna
50
Front display
80
Keypad
30
50 20
Top display
Controls top
30
(see Figure 3-3), UHF1 or 700,800
(see Figure 3-6)