I'm contemplating putting a hf radio on my catamaran. Choices seem to be between a marine SSB or a HF Ham radio. Ham radios can be modified for use on marine frequencies. Marine rigs can be modified for use on Ham frequencies. My problem is which way to go. Two major questions are (1) Can these radios be used to legally transmit outside their FCC approved frequencies (and if not legal, do many people do it anyway); and (2) how practical is it to use a modified marine radio on ham freqs (convenience, etc) and how practical is it to use a modified ham radio on marine freqs? In terms of cost, it seems less expensive to modify a ham radio such as an Icom 418 than to modify a marine radio. Any guidance would be appreciated. TIA, Dan
Since this IS my field and I AM an expert on this..
I'll state that a "modified ham radio rig" is legal to use in ham bands only.
It it not legal for amateurs or anyone else to modify radios to operate in "out of band" operation.
That does not mean you can't purchase radios that can operate in all bands though. You can.
I have a radio that CAN operate in both marine bands (actually it can pretty much transmit in any band) but it is ONLY operated in Amateur bands as that is what it was designed to do.
There's a little thing called "FCC Type acceptance".
Amateur radio gear is NOT(necessarily) FCC type accepted. Nearly all other equipment is. (Again, some ham radios are type accepted).
What this means is they meet certain specifications to prevent interference to other radio services.
If I'm not mistaken, you can find a few radios from several large manufacturers that will cover, legally, both the amateur bands and the marine frequencies you require.
Personally, I'd do a bit more research on the radio gear.
Lastly - you need to decide what you need to use the radio for. If you are a ham, you need to have an Amateur Radio Operators license. If you are going to use Marine, you need a restricted operators license (no test, just a fee) and a ships radio station license (fee, no test). Ham radio requires you have at minimum a General class license (not a HARD test, but not EASY either).
(For the record I hold a RR license, and I hold an Amateur Extra license. I've held a First Class Radio Telephone Operators license in the past - no longer issued these days, and Second Class and a Third Class. Also for the record I've been involved in using, setting up and training radio systems for nearly forty years now.)