User's Manual
Table Of Contents
- 1 REGULATORY AND SAFETY INFORMATION
- 2 PREFACE
- 3 SPECIFICATIONS
- 4 GENERAL INFORMATION
- 5 OPERATION
- 5.1 CONVENTIONAL STATION CONFIGURATIONS
- 5.2 ENCRYPTED STATION CONFIGURATIONS
- 5.3 MODES OF OPERATION
- 5.4 ENCRYPTION FORMATS
- 5.5 P25 CONVENTIONAL CONFIGURATIONS
- 5.6 PROGRAMMABLE FEATURES FOR CONVENTIONAL STATIONS
- 5.6.1 Conventional Stations (Setup)
- 5.6.2 Main Station Data
- 5.6.3 Push-to-Talk Options
- 5.6.4 Other Potentiometer Settings
- 5.6.5 Carrier Control Timer
- 5.6.6 Squelch Tail Elimination
- 5.6.7 Drop Out Delay Timer
- 5.6.8 Control Shelf Options
- 5.6.9 Station Remote Control
- 5.6.10 Auxiliary Control Relay
- 5.6.11 Squelch Operated Relay
- 5.6.12 Channel Guard Monitor
- 5.6.13 System Module - Digital Signal Processing
- 6 MASTR III ADC STATION DESCRIPTION
MM102558V1 R1A
5.2.2 RF-Only Encryption/Decryption
In RF-Only Encryption/Decryption (E/D) stations, external encryption equipment is connected directly to
the MASTR III ADC station. The voice signal is always delivered clear (unencrypted) from the dispatch
center to the base station where it can then be encrypted and sent over the radio path to properly equipped
mobiles and portables. One or more station consoles operate in a standard clear mode, tone control
configuration.
In an RF only E/D station, the working cryptographic key must reside in the external encryption
equipment co-located at the MASTR III ADC station site. The external encryption equipment is remotely
controlled to select for CLEAR or GUARDED modes of operation at the start of each transmit PTT,
receive mode selection is automatic. Four-wire control is still a requirement but only a voice grade (not
data grade) circuit is required.
5.3 MODES OF OPERATION
Options are available for conventional MASTR III ADC stations to provide the following modes of
communication:
• Analog FM (Clear Voice)
• Data (Paging and other externally generated NRZ Data formats)
• Digital Voice (unencrypted AEGIS)
• Digital Voice Encryption (Encrypted Voice Guard or encrypted AEGIS)
5.3.1 Analog FM
When operating in conventional analog mode, the MASTR III ADC station communicates via traditional
FM modulation schemes. Narrowband (12.5 kHz) bandwidth is available on the VHF and UHF stations
while Wideband (25 kHz) bandwidth is available on the VHF, UHF and 800 MHz bands.
Both the TX and RX audio circuitry is designed to provide extremely clear audible speech characteristics
from 300 Hz to 3000 Hz, with sub-audible tone capability for Channel Guard requirements.
5.3.2 Data
The MASTR III ADC station may be equipped with a Data Module capable of delivering up to 9600 bps
Non-Return-to-Zero (NRZ) serial data transmissions. This mode of operation provides the necessary
digital interfacing required for paging and other externally generated data formats.
5.3.3 Digital Voice
The MASTR III ADC station may be equipped with an external Digital Voice Interface Unit (DVIU)
capable of encoding and decoding digital signaling. Stations equipped with the external DVIU can
provide one of several digital voice formats, each having certain types of encrypted or unencrypted
services available. The formats and types are as follows:
• Voice Guard (DES and VGE)
• AEGIS (Unencrypted AEGIS, Encrypted with DES, VGE or VGS)
• P25 Conventional (Unencrypted P25, Encrypted with DES and AES)
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