On 9/3/2013 3:05 PM, rickman wrote:
On 9/3/2013 2:07 PM, Jerry Stuckle wrote:
On 9/3/2013 12:47 PM, rickman wrote:
On 9/2/2013 1:11 AM, Fred McKenzie wrote:
In ,
wrote:

I doubt I'll be mounting this in a boat although that is a possibility
someday, I do have a ski boat. But more likely is that I'll mount
it at
my house on a lake to provide some amount of emergency monitoring.
So I
expect to mount it in the pickup so it can be easily removed and
brought
into the house. I guess that means a second antenna too.

Rick-

I am assuming you can manage the legal requirements for use of the
radio. As others mentioned, a license may be needed.

One question you must address, is what kind of range do you need to
cover? VHF radios are essentially line-of-sight. Due to the curvature
of the earth, the "radio horizon" will limit your range.

You can estimate the distance in miles to the radio horizon, as the
square root of twice the altitude of your antenna in feet. For example,
the antenna on the roof of your truck will be approximately five feet
off the ground. The square root of ten is about 3.2, so your horizon on
level ground will be about 3 miles away.

You can add the distance to the kayak's horizon to yours. So it would
matter if the kayak is on a mountainous stream or on the open ocean or
lake.

If vehicle mounting does not provide the range you need, a tall antenna
may be required at the house. (Have you considered using cell phones?)
ccc
Hi Fred, I appreciate the response.

I'm not sure there is a lot of value to calculating the line of sight
for the antenna mount. I don't have much choice in the mount other than
having to make it lower because of some practical consideration like
hitting bridges... As to need, I want the max I can get of course. The
other end of the link will all be handheld radios.

The kayaks will be on the Chesapeake Bay, but close to shore. So land
obstructions will be the limiting factor most of the time. At least it
seemed that way on prior trips. But I don't have a lot of experience
with the hand held units we used so I'm not sure what I should have
expected.

The sort of issue I'm more interested in discussing are things like what
type of antenna and how best to mount and connect it to the radio. Of
course, I'm interested in the radios if anyone here has experience with
them. I see 25 Watt (which I'm assuming is the max available) units at
the bottom end for just over $100 and others which seem to be similar in
regards to the specs I understand for over $200 and of course the prices
run upward too. Are there aspects I should look for that I need to dig
deeper into the specs to find? For example is there some spec on the
internals of the receiver that would make a weakly received signal more
clear than another radio? What about the speaker itself? Would it be
better to have an external speaker or is the internal speaker usually
ok?

I'm looking for advice from those who are experienced with marine VHF.
Of course, I don't know what I don't know, so I'm looking for help
figuring out the questions.


Rick,

You've answered a couple of questions here. First of all, you are in the
United States, so are governed by the FCC.

Marine radio licenses are not needed for the kayaks while on the river,
but land stations (i.e. your truck) would do.

You could be considered a "Private Coastal Station". You would have to
"provide a service to vessels..." to get this license. I'm not sure if
the FCC would consider talking to your kayaks to be "a service to
vessels" - I guess it could be argued that it is.

Another option would be a "Marine Utility Station" - these restricted to
handhelds with ten watts or less power. You still have to "provide a
service to vessels".

Another option would be the "General Mobile Radio Service". You don't
have to provide a service to vessels with this license, but it is
basically handhelds in the 1-5 watt range (and can have removable
antennas, so you could add an external antenna). You need a license
here, but family members can all operate under the same license
(individual licenses are not required).

Of course, every person operating a radio could get a ham license; you
would be much less restricted in your operation (power, frequencies,
etc.). You just can't use it for business - which it sounds like you
aren't. Each person would have to pass a test (not that hard and many
ham clubs around the country provide testing on a regular basis). Of
course, it gives you a lot of other options, also - like using a
repeater to extend the range of both the kayaks and your truck, assuming
one is available (I don't know what's available around the Chesapeake
River area, but this area is loaded with repeaters).

I hope this helps you with some ideas.

Jerry, yes, this helps a lot. Once I was told I needed the license I
found the FCC site to be less than clear. I appreciate you laying out
the options. I would like to have a more powerful transmitter than the
handhelds have, so I think I will research the Private Coastal Station.
One of the licenses mentioned on the FCC page says you can fill in the
form online and you effectively are licensed as soon as you make the
application. I believe this was the "marine utility station license",
but I can't find that info at the moment.

Does a private costal station have to be stationary? Could I swap the
unit between house and vehicle? Or do I need two licenses?


OK, I did a little more looking into the FCC regs (Part 80 governs
Maritime use). The supplemental restrictions for a Private Coastal
Station are listed at
http://www.ecfr.gov/cgi-bin/text-idx...1.78.1&idno=47.

It looks like you do not meet any of the requirements, so you would not
be eligible for such a license.

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Jerry Stuckle
JDS Computer Training Corp.

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