User's Manual

Table Of Contents
MM102558V1 R1A
5.6.9.3 Tone Remote
In tone remote applications, the T/R Shelf uses the System Module and its onboard Digital Signal
Processor (DSP) to interface with a Tone Remote control unit through a two-wire or four-wire phone line.
A MASTR III ADC station may be programmed to allow Tone Remote control of the following
functions:
Repeater Enable (disable)
Channel Guard Decode Enable (disable)
Channel Guard Monitor
Transmit Frequency Selection
Receive Frequency Selection
Scan
Receiver Selection (Auxiliary Receiver selection)
Auxiliary Output Enable (disable) (Auxiliary Control)
Signaling from a Tone Remote control unit consists of a high level Secur-it tone, followed by the
appropriate medium level function tone (as well as a hold tone if the transmitter is keyed). The tone
control sequence is shown in
Figure 5-3.
The Secur-it tone is a +10 dB, 2175 Hz tone that is present for 125 milliseconds. The Secur-it tone is
followed by a 40 millisecond, 0 dB Function tone. The Function tone can be followed by a 2175 Hz Hold
tone at -20 dB level if PTT is selected. The Hold tone is present as long as the PTT is pressed.
Figure 5-3: Tone Remote Control Signaling
The frequency of the Function tone determines the function selected by a tone remote control unit.
Function tones range from 1050 Hz to 2050 Hz, and are spaced 100 Hz apart.
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