As the most significant recreational fishing innovation in recent times, sonar fishfinder units are well established as a fundamental piece of equipment for boat-based anglers and, like almost everything electronic, decreasing size and increasing capabilities are expanding these applications by bringing the benefits of sonar technology to land-based fishing. One of the latest examples - the Humminbird Smartcast RF30 - utilises a wireless link between a small sonar transducer attached to the fishing line and a wrist-worn display unit to provide a picture of what's underneath - identifying fish within a 25 metre radius a well as a map of the bottom and any submerged structures that could cause snags.

The 22mm x 23mm display incorporates data on Fish ID and depth range plus afish alarm and can be used in conjunction with any rod and reel. The unitoperates to a depth of 30 metres and has a 90 degree sonar beam coverage, with real-time data transfer making it possible to "scope" a location byderiving an underwater map with a few quick casts.

Easy access to this type of data means that applications for the SmartcastRF30 go well beyond fishing. The unit can be used to check mooring depths, creek & river crossings while four-wheel driving, or to inspect dams forsilting and depth.

The floating Remote Sonar Sensor is fully waterproof and can be expected tolast 400 hours of in-the-water usage according to Humminbird.

Power is froma single cell replaceable battery that lasts 25 hours and a "wet switch"that automatically shuts down the Sensor when out of the water isincorporated to minimise power consumption.

A 'B' Remote Sonar Sensor that uses a different channel can also bepurchased so that two people can fish with individual SmartCast's in thesame area without signal interference.

The RF30 retails for AUD$215. See the Humminbird website www.humminbird.com.au or call 07 3890 1115 to learn more.