[bill erhardt]

I live on the Sea of Cortez in a sparsely populated area of the Baja peninsula in Mexico. It is not unusual to fish for one, or two, or three days offshore and not see another boat. A handful of fishermen maintain base vhf stations in their homes. With a regular 25 watt vhf unit one can usually maintain contact with somebody in another boat or ashore within 25 to 30 miles. I would like to increase that range, if it is practical. I think, but am not sure, that with a 2 meter radio comes an increase in power from 25 watts to 50 + or -, and a commensurate increase in range. My questions are:

1. Is it true that increased range in communicating with a regular marine band vhf radio can be achieved with a 2 meter radio?

2. Does a 2 meter radio require a different antennae than a regular 25 watt vhf marine band radio?

3. Is it possible/practical to mount a 2 meter radio on a center console fishing boat?

4. What unit would be recommended for either a base unit or a boat mounted 2 meter radio that would be used not for any other ham radio purpose but only to increase the range on marine band communication, and not also break the bank?

[Capt Rick Hiott]

Bill,,,I dont know if this will work in your area, but have you seen this?
http://www.seasmartvhf.com/

This post has been edited by Capt Rick Hiott: 15 September 2009 - 09:25 AM

[bill erhardt]

Bill,,,I dont know if this will work in your area, but have you seen this?
http://www.seasmartvhf.com/

Rick......This Seasmart service is apparently available in the continental US. I'm about 700 miles south of the border.

"As a Sea Smart subscriber you can use your boat's VHF to direct dial our marine operators, who will then patch your call through to anyone in the continental U.S., with no call limits or overage charges. Ship-to-shore phone calls are now available. With the key of your VHF's mic, you're connected."

Also, it apparently relies on DSC technology. In my experience the range on DSC communication is, if anything, a little less than regular vhf communicaton.

"As a Sea Smart subscriber, you will receive your own, unique MMSI number that contains all your boat's pertinent information. And because your DSC-enabled VHF is connected to your GPS, Sea Smart can send that information directly to your home or office computer. Vessel location, trip tracking and poll positioning are now available. With a click of the mouse, you're connected."

[welder]

Bill , my I.T. guy , Bill Thomson on my forum [ www.aluminumalloyboats.com ]is a HAM for 41 years now .

He can answer your questions , I will also try and send him this way tonight.

I do know the 2 Meter is a whole nuther critter to play with.

This post has been edited by welder: 22 September 2009 - 12:18 AM

[welder]

> I live on the Sea of Cortez in a sparsely populated area of the Baja > peninsula in Mexico. It is not unusual to fish for one, or two, or > three days offshore and not see another boat. A handful of fishermen > maintain base vhf stations in their homes. With a regular 25 watt vhf > unit one can usually maintain contact with somebody in another boat or > ashore within 25 to 30 miles. I would like to increase that range, if > it is practical. I think, but am not sure, that with a 2 meter radio > comes an increase in power from 25 watts to 50 + or -, and a > commensurate increase in range. My questions are:
>
> 1. Is it true that increased range in communicating with a regular > marine band vhf radio can be achieved with a 2 meter radio?
>
> 2. Does a 2 meter radio require a different antennae than a regular 25 > watt vhf marine band radio?
>
> 3. Is it possible/practical to mount a 2 meter radio on a center > console fishing boat?
>
> 4. What unit would be recommended for either a base unit or a boat > mounted 2 meter radio that would be used not for any other ham radio > purpose but only to increase the range on marine band communication, > and not also break the bank?
Hello Bill,

Yes, 2 most 2 meter mobile radios ARE capable of 50 watt output, BUT...

A license is required to (legally) operate the transmitter. Since you live in an area controlled
by Mexico, you'd need a Mexican Amateur Radio license. But even at that, what you seek to do isn't
possible, unless all parties who want to talk to each other use 2 meter radios.

VHF radio signals operate on the "line-of-sight" principle. Atmospheric bending extends the range by about
10-15%, so even at 50 watts of output, the range will be comparable to that of a VHF Marine radio.
1. 2 meter and Marine VHF radios operate on different frequencies, so can't "talk" to one another.
Gross simplification: it would be like calling someone on Marine VHF channel 16, but they are listening on channel 10.
With 2 meters, the frequency difference is MUCH greater than the example I just gave, but the principle is the same.

2. Yes, the 2 meter radio requires a different antenna.
3. Yes. The radios are typically mounted in road vehicles of many types and sizes, so mounting one in a CC boat
shouldn't pose a problem space-wise.

4. A 2 meter radio would be of little or no use unless you plan on talking with other hams, or others that have
2 meter radios.

Hope this helps,

Bill Thomson

[bill erhardt]

Welder........Thanks for running this past Bill Thompson, and give him my thanks, as well. I ran these questions up the flag pole at THT, and the responses were pretty much consistent with what Bill said. http://www.thehulltruth.com/marine-electro...ter-radios.html The consensus was that I should focus on antennae to improve range on vhf communication. I've decided to live what what I presently have on my boat, which is an ICOM 422 and an 8' Digital 6 db antenna, and have ordered an 18' 9 db antenna to replace the 6 db 8' whip I presently have on my base unit. As luck would have it, a friend recently bought a new boat in the States with a flush deck that he is bringing to Mexico, and the new 9 db two piece 18' antenna will be delivered to him in Phoenix today for the trip down. I should have it next week.

This post has been edited by bill erhardt: 22 September 2009 - 03:14 PM

[Kamper]

I've been thinking about this problem whenever I logged in over the past couple days. Even if you had been able to boost the transmit power of your VHF signal the odds would be against the other boat having similiar VHF performance. This would still have some value in getting out the word if you were in distress but you wouldn't be able to co-ordinate the efforts until they got lots closer.

I see where you've accepted Welder's antenna suggestion. Most of what I've read indicates that the higher and better the antenna the better your VHF performance will be.

Having said that... It finally clicked what I've been overlooking. VHF is not the only maritime radio band. VHF/Very High frequency is most common and operates in the 30-300 MHz band (I have 'Chapman's' open in front of me). MF/Medium Frequency 300-3000 kHz (3000 kHz = 3MHz). HF/High Frequency 3-30MHz. These numbers really don't mean much to me but an expert will tell you they permit communications out to various maximum distances. Additionally SSB/Single Side Band type hardware offers advantages for signal between 300kHZ-30MHz. Outputs of 150 watts are normal.

Where VHF is mostly line-of-sight, signals in these lower bands are reflected off the ionosphere and permit communications well beyond the horizon. This won't help you to reach those VHF base stations but should reach commercial vessels if you need assistance.

The downside to these units is the expense. $2000 and up is not unusual. I don't know if your Mexican station license covers this type of gear but you probably know who to ask about that, down there.

Good luck!

This post has been edited by Kamper: 22 September 2009 - 03:56 PM

[chemoniepilot]

2 meter equipment is limited to ham radio and emergency ham radio operations. Marine VHF is limited to boating/fishing/hollering for help type talk --- two totally different purposes.