Introduction

The RTcom-range of radio modem is intended as a direct replacement for cables over short, medium and long distance, serial data links. They are suitable for part of point-to-point, master to slave or scanning telemetry links, where the modem is either used on its own our in conjunction with existing cables. The modems also operate transparent to many industry standard network protocols, such as Modbus and Eiba Bus and can be used with many manufacturers PLC communication protocols.

Serial Data	Serial Data
RTcom	RTcom
Modem	Modem

Fig 1: Simple point to point link

The advantages of wire free communication offered by Radio Modems such as Radio-Tech Universal, Global, Europa, Outback and Max are numerous. These include reduced installation cost, the ability to cross-awkward terrain, cross third parties lands, cross-rivers and operate from moving objects.

RTcom	Slave Station (1)
Modem
RTcom
Modem
Master station
RTcom	Slave Station (2)
Modem

Polled Master to multiple slave system

Thousands or RTcom radio modems are now in service throughout the world, many operating 24hrs a

day, all year round. However, for any radio communications system to be reliable care should be

taken in the design of the whole system. Many countries impose restrictions on the frequency, power,

channel power and occupied bandwidth of transmissions. Others in addition impose strict test and

certification procedures on equipment while others permit a free for all!