User manual

AGM Spread Spectrum Radio Manual
4
Introduction
Overview
The AGM AUX/DIN 5017-1 SSR is a low cost radio modem using spread spectrum
technology, operating in the 900 MHz band. The SSR complies with FCC Part 15 rules and
may be operated without licensing. The SSR is intended for short range line of sight
communications of up to 20 miles using external high gain antenna.
The SSR may be wired either for a RS485 or RS232 system. When used with RS485 the
SSR will automatically switch to RS232 for configuration. Either full RS232 or 3 wire RS232
may be used.
The standard SSR communicates over the air waves at 9600 bps. 19200 and 1200 bps are
available on special order.
Default communications is set for 9600 bps, 8 data bits, no parity and 1 stop bit. The SSR
may also be configured for 1200, 2400, 4800, 19200, 38400, or 57600 bps. 7 bit and 8 bit
parity options are also available through configuration.
Theory of Operation and Construction
The heart of the SSR is an industrial hardened radio modem that groups received characters
into packets, adds error checking, and then transmits the packet using spread spectrum
frequency hopping algorithms. Other SSR receive the transmitted packet, checks the packet
for errors and then if no errors sends the received characters to the connected device. The
use of spread spectrum frequency hopping algorithms allows multiple radios to share the
same frequency band with minimal interference.
The SSR may be used with any protocol that uses 7 or 8 bit asynchronous data. This
includes but is not limited to: ASCII Modbus, RTU Modbus, DF1, or DNP3. You do not need
to own AGM Electronics Inc. equipment to use the SSR.
The SSR is configured by using a computer and any terminal emulation software such as
Hyperterminal which is packaged with Microsoft Windows. The SSR may be configured in
the field using a laptop computer and RS232 cable. A RS232 to RS485 adapter is not
required to configure the SSR for RS485 installations.
In most installations, the SSR can be used right out of the box, however AGM Electronics Inc.
will configure your SSR at the factory free of charge.
The hermetically sealed assembly minimizes installation costs.