Re: VHF Radio
How well VHF Marine Radio works really depends on where you are boating. On small inland lakes and small rivers I find very little use.
Along the Coast and large lakes and large rivers with Commercial Traffic then a VHF Marine Radio is a must.
I feel the First VHF Marine Radio Should be a 25 watt Fixed mount with a 8 foot 6DB Gain antenna. This gives you a Effective Radiated Power (ERP) out of 100 watts.
With the antenna mounted about 3 feet above the water you will have a range of about 4.7 miles plus the range of the other station. So boat to boat is about 10 miles.
For sail boats a 3 foot 3 db gain antenna mounted on the mast head is best.
Boat to the Coast Guard Range along the coast out here is about 80 miles because the Coast Guard antennas are mounted on high mountains top as high as 3000 feet.
All new Fixed mount VHF Marine Radios must have DSC Distress button.
If you have a MMSI Identification Number in your radio and have it connected to a GPS then pressing the DSC Distress button will start sending out a Distress call on channel 70. If the Coast Guard receives this automatic distress message they will know where you are and information about your boat. Even if your out of range of the Coast Guard every boat with a DSC Vhf Radio will also get your distress call and their radio will automatically send your message out so if they are in range of the Coast Guard they will get your message. At this point Rescue 21 the Coast Guards name for DSC Distress call is not in place in many areas but they are working to get full coverage of the entire coast of the USA and some inland areas. You radio will keep sending the Distress message out until it gets a reply from a land station. When the coast guard get this message they will try to call you on Channel 16. So while your trying to plug the leak and bail water out of the boat or trying to put out the fire your radio is sending a distress call.
Handheld VHF Marine Radios have 5 or 6 watts of power and transmit into a rubber duck antenna that is about minus 3 DB loss for a (ERP) of about 3 watts.
The range depends on how high off the water your get the radio but for most about 2 miles plus the range of the other station. I have not seen a Handheld that has DSC Distress button yet.
You handheld your must stop what your are doing a make a MAYDAY call tell them where you are.
Cell Phones in some area may be better than a VHF Marine Radios if there is no one who has a vhf radio but would be my last choice. If you are sinking or on fire how do you call the boat ? mile from your position. Offshore Cell phone only work for a very shore range. There are no cell towers 5 miles out. Flare require someone to be looking your way and they do not work in the fog. Even if seen what you usually here on the radio is we Believe we saw a red flare to our south. Coast Guard usually replies, Keep a sharp look out and report any additional sittings.
I agree that the antenna is more important than the radio. The first antenna I got was 8 foot and 6 db gain but small around an felexable. I would be fishing near other boats and could here there radio. I would scan all the channels and not pick them up. I double checked the Standwave ratio with a bridge and everything looked good.
Finally I just bought a shakespeer 5225 antenna. First trip out I could not believe the different I could here everything. At the dock people would ask me what channel I was picking up all the fishing traffic on. I would explain it is the antenna not the radio or channel.
For poeple who want the best VHF DSC radios get one with a CLASS D DSC. This gives you a seperate channel channel 70 for DSC distress calls or polling to see where your buddy is fishing without calling on the radio.
I also carry 2 handhelds VHF radios. One in our survival bag and the other on the dash.
One in the bag sealed in a heavy zip lock bag.
Below you will see three links to a Coast Guard commander talking about how DSC works.
http://www.youtube.com/watch?v=M-f4nhnBThg
http://www.youtube.com/watch?v=mdkxsWBncSc&feature=related
http://www.youtube.com/watch?v=JQk5MRwuxgo&feature=channel