Radio modems are a convenient way of linking two devices without having to lay a cable, making such things as ship to shore and mobile telemetry possible.  They do not require a license (when used at 0.5W) or have line rental or call costs.  They are simple to install, rugged in design and have a proven reliability that makes them a world leader in this field, and have a selectable RS232, RS422 or RS485 interface and from 0.5 Watt up to 10 Watts of power.

Most units are approved worldwide, although some country specific regulations apply and these are worth looking into before installation. Certificates of conformity and copies of approval certificates can be provided upon request.

How far do they go?

Some environmental and installation restrictions have to be taken into consideration when planning a radio data network as this can affect range. Our experienced team is always pleased to discuss individual requirements to offer the best solution. 

There are many claims and calculations of radio range made, and when looking at these figures, it must be remembered that these are quoted in 100% ideal conditions i.e. clear line of sight, good weather conditions, correctly tuned and placed antennas, very low loss cable etc. In our experience, it is very rare that all the conditions can be met to achieve the perfect installation, and whilst in theory ranges of 20km are possible, these are few and far between, a more realistic view is around 3-5km at 0.5W using a 0 gain omni-directional antenna. This can be extended with a directional (Yagi) antenna, so long as the radiated power is maintained at 0.5W.

Most of the Satel radio modems have addressing as standard, enabling them to be used in a radio data network.  Addresses for transmit or receive do no not necessarily have to be the same and so they can also be used to extend the range of a network by acting as a repeater.

Although not recommended as it can effect reliability, the units can also work without handshaking, and can operate on a two wire system providing that the radio channel is free and the length of the data packet does not exceed 1 kilobyte.

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Page last updated 8 June 2008 : Specifications subject to change without notice : E & OE