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. Normally our modems will work satisfactorily with a signal level below 1uV
INSTALLATION
Power Supplies:
As with any radio communications system, the RTcom modem should be connected to a clean and stable supply. Switch mode power supplies are rich in RF harmonics and should not be used. Please note that in many cases as CE sticker on a power supply is insufficient protection against potentially damaging harmonics. The reality is that the EMC pass limits are set at only
Location:
For indoor installations we recommend that the modem is located away from sources of heat and electrical apparatus such as inverters. Care has to be taken to minimise cable lengths both with respect to the antenna location and the attached terminal equipment. Generally RS232 should be used for short distance links < 30ft (10m) and RS422 / RS485 for long links of up to 1000ft (300m). In practice the maximum distance achievable will depend upon the combination of the drive capability of both the modem and data terminal.
The IP65 rating of the modem enclosure would to many imply that it could be operated outdoors in all weather conditions. Experience has shown this to be true, but operation can be jeopardised through long term exposure to rain, frost, direct sunlight, chemicals and blown sand. For these reasons we also recommend that where possible the modem should be mounted within a second enclosure of a similar IP rating and where the climate is variable a thermostatically controlled
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