Hey psion.  You don't need a license to use a 27meg.  You do need one for the VHF (except in the case of an emergency).  27 meg sounds crap, and VHF sounds great and goes much further.  If you decide on a VHF, please at the very least, read the MROVCP handbook and be sure you know how to use it.  I get so annoyed at the people calling VMR on VHF and have no idea how to talk radio talk.  It wastes air time.

On a jet skit, you could maybe get away with a handheld VHF.

edit: also make sure you do the course at a sea rescue to support them.  And get your membership so that you get a call sign. I did mine at Fremantle and it was a good course.  Practice your phonetics beforehand.

Do some research on what brand to buy, some are rated to a metre under water for 5 minutes so should be suitable for a jetski. Don't bother with 27 meg, most groups up north if you are going to head up this way don't monitor it.

Still waiting on a Federal level reply for recreational use of VHF radios not requiring a licence. The best way to get a licence is to join up at your local sea rescue unit as a vollie and make yourself available for duty and they can run you through the course, usually for their cost of around $140 that they have to pay for books and registration.

Great info as usual, I will do the course, and find a waterprrof one. will also contact the sea rescue guys and chat to them, signing up sounds like a good idea. Will check it out when I get home

cheers

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This is probably the best deal you will find online.  I purchased from this company and found them great.  I got distracted whilst wiring it up and damaged the unit.  They replaced it for free!