Hi again Muroc,
I am pleased you found my answer helpfull. It has occures to me though that I should have added a little more about transponders, such as SeaMe. These devices are not cheap, costing about £400 but they are good. The great advantage with a transponder, apart from being seen, is that in normal operations it draws very little current as it operates in "receive only" mode. Once a RADAR signal is received it goes into transmit mode. Alson, it gives a signal indicating that it has picked up a vessels RADAR signal, which is a good warning of trafic in the vicinity.
What is the disadvantage? Well, apart from not being a RADAR as such, thus not being able to indcate the direction and range of the vessel from which a signal has been receved, it operates only on one wavelength. Maritime RADAR operates on either 3 or 10 cm. wavelength. Normally ships use 10cm but at shorter distances 3cm. The advanced RADAR sets big ships use change the wavelength automatically as the range is changed. This means that the transponder will only be picked up on the 10cm. wavelength. Is this a problem? Well, not normally. Looka arround at big ships and you will see that they are fitted with at least two RADAR sets. They usually have one set at longer (10cm) range and one at closer 3cm. range.
Once again, good look with the boat.