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SYSTEM FEATURES & OPERATION
Introduction
The 7720PLUS self-contained synthesized subscriber radio is the subscriber end of a Long Range
Radio alarm reporting system. As a communications link, by analogy to a telephone-based system,
the 7720PLUS is comparable to a digital communicator connected by telephone line to a central
monitoring station.
Synthesized Frequency Selection
The 7720PLUS can be programmed to operate on any authorized radio frequency. It is not
necessary to stock a separate radio for each frequency the installer supports.
Wireless Reporting
All alarm and status messages are transmitted to the master station network via radio signals, which
means faster and more secure reporting.
Integrated Electronics
The entire radio link equipment, except for the AC power supply unit, including interface,
transmitter, battery and antenna, is housed in a single package, requiring only alarm inputs from a
compatible alarm panel.
Selection of Input Interfaces
The 7720PLUS can monitor alarm inputs from the Ademco ECP interface, discrete 4 zone contact
closures or their electrical equivalent
NOTE: ECP features are compatible only with 685 software revision 4.7 and higher, and
685-5 software revision 8.1 and higher.
Compatibility
The 7720PLUS is compatible with existing installations using ADEMCO equipment or other control
panels. The 7720PLUS can be used in conjunction with digital communicators on the same system,
both acting as backup to one another (use an ADEMCO 659-EN Line Monitor connected to a zone
input to report a line cut to backup a digital dialer), while connecting the radio fault output to a zone
on the dialer.
Built-in LED Indicators
Three LEDs are used to indicate message transmissions, and radio faults. A blinking yellow LED
indicates normal operation. (See LED Table Page 4).
Built-in Tamper Protection
For added protection, built-in cover tamper switches will trigger an alarm whenever the chassis cover
is removed, thus protecting against unauthorized access to the 7720PLUS. The tamper zone number
must be entered during programming to enable tamper reporting. A radio configured for ECP will
automatically report the tamper status to the control panel, as well as to the Central Station
Antenna Included
The 7720PLUS can use either the supplied omni-directional wire antenna, or can use a 7825 outdoor
antenna, 7625 omni-directional antenna, 7625-3DB antenna (if additional gain is required), a 7674, a
7674-13 YAGI antenna (if a directional antenna is required), by using the optional 7720ANT
connector kit. For wall mounting, an optional 7825DP can be used. The supplied antenna mounts
directly to the7720PLUS. The antennas (other than the wire and the dipole) can be mounted
remotely, if desired, using the following pre-assembled coaxial cable, available from ADEMCO: 5ft
