boater2065
Active Member
@b_arrington Thank you for that helpful information, much appreciated.
VHF Question
- Thread starter boater2065
- Start date
Regardless of the radio's power, range is really dependent upon the antenna gain.
High gain antenna's have a very narrow transmitting width but long range capability so not really good for in-shore and close communications. A friends Viking has a 9db antenna and cannot contact the marina he is at when near; He has to use a different VHF with a lower gain antenna. Off shore however, he is the cats meow.
Low gain, on the other hand, has very good close quarters coverage but reduced range.
For in-shore boating I would stay between 4db and 6db antenna gain.
High gain antenna's have a very narrow transmitting width but long range capability so not really good for in-shore and close communications. A friends Viking has a 9db antenna and cannot contact the marina he is at when near; He has to use a different VHF with a lower gain antenna. Off shore however, he is the cats meow.
Low gain, on the other hand, has very good close quarters coverage but reduced range.
For in-shore boating I would stay between 4db and 6db antenna gain.
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Other way to say this that high-gain antennas are basically highly directional, and low gain are omnidirectional. Sail boats need a low gain antenna on the mast. If they used a high gain, when heeling over in the wind they would basically transmit into the sky and the water.
While the effect is less severe, power boats can be impacted by this as well. Your running angle can impact transmissions with a high gain antenna - if your antenna tips back. Also if you are rocking back and forth in seas, the transmission from a high gain antenna will cut in and out. It can give really long range but does have some drawbacks.
While the effect is less severe, power boats can be impacted by this as well. Your running angle can impact transmissions with a high gain antenna - if your antenna tips back. Also if you are rocking back and forth in seas, the transmission from a high gain antenna will cut in and out. It can give really long range but does have some drawbacks.
boater2065
Active Member
FYI, I was able to take the existing MMSI number and register it to my Boat US membership. It was very easy to do and doesn't require changing the number or sending the radio in etc. All i did was email MMSI@boatus.com about my issue. They looked up the existing number and reset the account so i could log into it. Once logged in, i registered that number with my Boat US account, filled out some information about the boat and it was done.
RollerCoastr
Well-Known Member
- Nov 15, 2007
- 3,884
- Boat Info
- 1997 400DA
340HP 7.4 Mercruiser Bluewaters
Garmin 741, 742, 8212, 24HD, Intellian I2
- Engines
- 1999 280BR
Twin 250HP Merc 350 Alpha Ones
I assume the PO released it. That's awesome! That's a nice radio - now you know it works and have the MMSI data correct. That puts you ahead of at least 90% of boat owners. (sad, but an actual fact)
A new habit to get into will be a quick introduction to give to passengers about how and when to use the Distress button to call for help. Include children. If they're old enough to dial 911, then they should know about the Distress button too.
In fact, the less a passenger knows about boating or the area, the more important that discussion is.
You can also become part of the grass-roots movement to increase awareness of this powerful yet simple and inexpensive safety feature. The more boats that get it, the more safe we all are. If you cruise with friends or a club, you can collect their MMSI numbers and:
- Initiate a digital call to a given boat. That boat's VHF will ring like a phone, so they'll hear it regardless of squelch, volume or channel settings. (then both radios switch to a regular working channel for dialogue)
- Initiate a digital call to a GROUP of boats.
- Send a Position request to a vessel - their position will appear on your connected MFD, much like AIS target do. "Hey Aqua-hull-ick - push that throttle a little and get over here, the rest of us are docked and on our 3rd beer."
A new habit to get into will be a quick introduction to give to passengers about how and when to use the Distress button to call for help. Include children. If they're old enough to dial 911, then they should know about the Distress button too.
In fact, the less a passenger knows about boating or the area, the more important that discussion is.
You can also become part of the grass-roots movement to increase awareness of this powerful yet simple and inexpensive safety feature. The more boats that get it, the more safe we all are. If you cruise with friends or a club, you can collect their MMSI numbers and:
- Initiate a digital call to a given boat. That boat's VHF will ring like a phone, so they'll hear it regardless of squelch, volume or channel settings. (then both radios switch to a regular working channel for dialogue)
- Initiate a digital call to a GROUP of boats.
- Send a Position request to a vessel - their position will appear on your connected MFD, much like AIS target do. "Hey Aqua-hull-ick - push that throttle a little and get over here, the rest of us are docked and on our 3rd beer."
boater2065
Active Member
OMG, Aqua-hull-ick, i think we just found our new vessel name!
Definitely agree about the safety awareness. I grew up on ski/wake boats and mostly stayed close to our home bay so i never dealt with VHF or worried much about breakdowns because we were isolated in a small quiet bay. But now that i have this boat with plans to travel up the Sound (with young kids), i absolutely wanted VHF/GPS etc for any sort of issues we may run into. I will have to explain the distress switch to my wife and the 5 year old so they are aware of what to do in an emergency.
Digging through the VHF i have seen the options for calling individual boats in my radar. Super cool feature that I will have to try out sometime.
Definitely agree about the safety awareness. I grew up on ski/wake boats and mostly stayed close to our home bay so i never dealt with VHF or worried much about breakdowns because we were isolated in a small quiet bay. But now that i have this boat with plans to travel up the Sound (with young kids), i absolutely wanted VHF/GPS etc for any sort of issues we may run into. I will have to explain the distress switch to my wife and the 5 year old so they are aware of what to do in an emergency.
Digging through the VHF i have seen the options for calling individual boats in my radar. Super cool feature that I will have to try out sometime.