Instruction/ maintenance manual of the product Radio Modems RTcom
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User Manual RTcom-Universal, Global Max and Outback Radio Modems Copyright Radio-Tech Limited 1998-2000.
2 CONTENTS INTRODCUTION 3 Selecting the frequency of operation 5 R.F Path Surveys 5 INSTALLATION Power Supplies 6 Location 6 Antenna Feeders 7 Lightning Surge Protection 8 Antenna Installation 9 Anten.
3 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.
4 In many countries it is quite legal to operate systems without need for operating licences. These countries include the United Kingdom, Australia, New Zealand, Korea, South Africa, Scandinavia and the majority of Europe.
5 Frequency of operation Often there is not a choice over operating frequency. In most countries frequency allocations are very limited, by way of example in Europe there is only 433-435MHz UHF or 868-870MHz SHF. While the UK and many others offer VHF, UHF and SHF allocations.
6 If there is doubt over the signal reaching the receiver a path survey should be conducted. The outback modem includes a test mode that places the modems transmitter into constant transmit mode. This permits the measurement of signal strength at the receiver.
7 For battery powered operation in cold and damp climates the only reliable way to achieve long term operation is to use double IP65/7 enclosures, with both the outer and inner enclosure fitted with silica gel desiccant sachets. Please be aware that solar heating and wind chill can take the modem beyond its designed operating temperature range.
8 Lightning Surge Protection: A direct lightning strike can never be totally protected against or predicted. Currents exceeding 10,000A can flow vaporising antenna, feeders, towers and other such structures. Lightning conductors will give a degree of protection to the building but not always to the electronic apparatus within.
9 Antenna Installation The type and location of the antenna used can have a profound effect on your overall system performance and its legality. In point to point links it is good practice to make efficient use of the radio spectrum by selecting an antenna that will project the R.
10 Warning : The use of gain antenna in some countries is not permitted. Similarly where ERP (transmitted power limits) are imposed the actual transmitted power must not exceed the limit stated. This means that the transmitter output power, less any coaxial feeder losses, plus the antenna gain must not exceed the specified maximum ERP.
11 Guide to your RTcom-Global & Max Modem Status LED's 12-24V dc supply RS422 & RS485 Interface RS232 interface Links to select 2-4 wire RS485 Mode Switch for Data Rate and data format Ch.
12 Guide to your RTcom-Outback Guide to your RTcom-Max (Please take care when opening cover) Optional Location for Battery Solar/12-24V dc supply RS422 & RS485 Interface RS232 interface Links to s.
13 CONNECTIONS Data connections should always be made using screened cable. This will insure maximum rejection of interference from outside sources. Always use a common ground point. The RTcom Global, Eurpoa, MAX and Outback modems support RS232, RS422 and RS485 communications, both 2 and 4-wire.
14 Pin Number Designation WRT Modem Notes 1 DCD Optional not normally needed 2 RX (data) RS232 input data to modem 3 TX(data) RS232 output data from modem 4 RTS Optional not normally needed 5 GND Ground 6 B RX(-) RS485/RS422 7 A RX(+) " 8 +Vs Supply 7.
15 On the Global and Max modems two dip switches are provided for the selection of the desired operating mode and two plug links are provided from the selection of 2 or 4 wire RS485 operation. A further DIP switch is provided on the Global modem for frequency Channel selection.
16 OPERATION The RTcom protocol permits 100% transparent operation and direct cable emulation. Simply what goes in comes out! R.F. packet framing, code balancing, encryption and preambles etc are taken care of automatically within the modem.
17 COMMISSIONING The data rate, parity and number of data bits are set using the dual in line switch located above. If a scanner is available the chosen channels and the adjacent channels should be scanned for activity.
18 system. This results in the messages becoming fragmented, thus confusing the modem into thinking the end of file has been detected. The other common problem, in particular with WindowsTM Hyper Terminal, is the way in which is deals with errors.
An important point after buying a device RTcom Radio Modems (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought RTcom Radio Modems yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data RTcom Radio Modems - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, RTcom Radio Modems you will learn all the available features of the product, as well as information on its operation. The information that you get RTcom Radio Modems will certainly help you make a decision on the purchase.
If you already are a holder of RTcom Radio Modems, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime RTcom Radio Modems.
However, one of the most important roles played by the user manual is to help in solving problems with RTcom Radio Modems. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device RTcom Radio Modems along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
