Antennas

[cehart]

Have a tinny and am considering fitting a radio for compliancy purposes.

From what I have read it appears that I need a ground dependant (GD) antenna, but a tour of one of the local boat yards I noted a lot of alloy boats had which what looked like normal plastic bases ( could be mistaken here) with aerials of varing sizes where as most of the ground dependant ones are rather small ie 600mm or there abouts.

The GD bases look like there is sometype of metal band which I would assume would be in contact with the hull

Questions

Will this cause any issues with electrolysis and given that the radio is based on line of sight how would I go with such a small aerial as from what I have read its recommended to mount as high as possible, difficult on a open boat.

Someone with alot more knowledge than what I have may care to enlighten me

Cheers

[Noelm]

a "normal" non ground dependant antenna will work perfectly OK on a tinny, as will a ground dependant antenna, for best reception/transmission, the antenna needs to be as high as possible, be vertical and as long as possible, however, it also needs to be practical.

[Noelm]

I have posted this before, have a bit of a read of this.
http://www.boat-project.com/tutorials/vhfant.htm