SET UP A RADAR

Mention radar and most people think fog. Technically, fog starts at visibility of less than 1,000m and significantly changes your responsibilities under the collision regulations, the most pertinent being that we all move from being either a stand-on or give-way vessel to ALL being give-way vessels.

Setting up your radar correctly is crucial to its performance and is best done in clear weather with visible targets so you can see the changes to the picture as you adjust the settings. It’s important to do this before you encounter any fog otherwise how will you know it’s working correctly? Settings are adjusted either with individual buttons or soft keys. The major variables are range, brightness, gain, tuning and sea and rain clutter.

The first one to adjust is range as it needs to be set relative to your location. In a harbour, half a mile is usually about right. Next up is gain, which adjusts the sensitivity a bit like squelch on a VHF; too much and the picture becomes a mass of targets, too little and things disappear. Tuning is next, and you are looking for a crisp image of a nice hard target.

Now try all that again at a different range; older sets often need adjustment with every range change. More modern sets usually have an auto-tune function but it’s still worth seeing if this gives a better or worse picture than yours.