Racal Instruments AN/TRC-207, Инструкция по эксплуатации и обслуживанию

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TO 31R2-2TRC207-1
1-3
CHAPTER 1 GENERAL INFORMATION
1-1 DESCRIPTION AND PURPOSE.
1-1.1 Equipment Function and Purpose
Radio Set AN/TRC-6728 (hereinafter referred to as the bi-directional repeater or BDR) is a communications unit capable
of operating in the 30-88, 136-174, or 403-470 Megahertz (MHz) frequency bands. It is used to extend the
communications range of fixed, mobile, or portable receiver-transmitters. The BDR is COMSEC (Communications
Security) transparent and provides repeater capability for all modes without the need for COMSEC encryption/decryption.
1-1.2 Equipment Description
(See Figure 1-1.) The BDR includes a bi-directional repeater assembly, two non-CCI (Controlled Cryptographic Item)
Receiver-Transmitter Sets, Radio RT-1695/TRC-199 (hereinafter referred to as the receiver-transmitters), three antenna
systems, an antenna mast, three diplexers, a tubular (weldment) frame, a power supply enclosure, and a battery enclosure.
1-1.2.1 BDR Unit.
(See Figure 7-2.) The BDR unit includes three circuit card assemblies (CCAs) that are accessible through a removable
cover on the underside of the unit. These are the +15 volt (V) DC-DC converter CCA (A1), repeater control/audio CCA
(A2), and repeater interface (A3). These CCAs plug into the parent board (A4), which interfaces with the control panel
assembly (A5), power amplifier assembly (A6), the RF matrix CCA (A7), the external power supply, and the plug-in
receiver-transmitters. The receiver-transmitters plug into sleeves (A8, A9) located on the left and right sides of the front
panel of the BDR unit. The power amplifier (A6) is mounted under a heatsink on top of the BDR unit.
1-1.2.2 Receiver-Transmitters.
(See Figure 1-2.) The receiver-transmitters provide transmit/receive communication in the 30-88, 136-174, or 403-470
MHz frequency bands. The operating band of the receiver-transmitters is determined by the transceiver module installed.
When the transceiver modules are changed, the BDR must be fitted with the proper antenna and diplexer. The proper
configurations are listed in Table 1-1.
Table 1-1. BDR Configurations (by Frequency Band)
Frequency Band Receiver-Transmitter Antenna Diplexer
30-88 MHz
136-174 MHz
403-470 MHz SS-4100820-501
SS-4100821-501
SS-4100822-501 4242-MK2-RAC
4265-RAC
4266-RAC SS-1600322-501
SS-1600322-502
SS-1600322-503
NOTE
The CCI Receiver-Transmitter RT-1696/U(C) is mechanically different from the RT-1695/TRC-
199 to prevent full insertion into the BDR sleeves to avoid the possibility of leaving a CCI radio
in an unattended repeater.
1-1.2.3 Antenna Assembly.
The BDR antenna system provides half-duplex transmit and receive capability over one of three bands of operation. The
selected antenna is mast mounted. Three antennas are provided to cover the three bands of operation. Refer to Table 1-1.
A mast is provided to elevate the selected antenna up to 10 feet (in 5 foot increments) to increase transmission range and
quality of transmitted and received signals. The antennas and mast can be installed on a roof or existing tower to further
increase range.