Motorola ASTRO Digital Spectra, Instruction Manual

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6881086C22-B 19
Theory of Operation
Introduction
This section explains the general operation of the ASTRO Spectra/Spectra
Plus Consolette. For more detailed information about the ASTRO transceiver,
refer to the applicable ASTRO Spectra/Spectra Plus operator’s manual or
service manual.
Provisions have been made for the connection of voice recorders to the
ASTRO Spectra/Spectra Plus Consolette.
General
The ASTRO Spectra/Spectra Plus Consolette consists of three major building
blocks: the ASTRO transceiver, the Audio Interface or optional Tone Remote
Control board, and the power supply. The Audio Interface board is standard for
the Consolette. The Tone Remote Control board replaces the Audio Interface
board when the L146 option is added. All other blocks contained within the
Consolette are served by the three major building blocks shown in bold (see
Figure 5).
Figure 5. Consolette Block Diagram
Each major building block has its own unique function:
• Modulation, demodulation, and all other RF signal processing are
performed by the ASTRO transceiver.
• All baseband signals being routed to and from the radio pass through the
Audio Interface board or optional Tone Remote Control board. The board
provides an interface for the ASTRO control head, speaker, accessory
connectors, and other options.
Audio Interface Board/
Tone Remote Control Board
ASTRO
Transceiver
Fan
Accessory
Connectors
Power Supply
ASTRO
Control Head
Power On
LED
VU Meter/Clock
(Option)
Speaker