VHF antenna location

Barquito · #1 (**permalink**) 01-19-2011

I am going to install a fixed VHF, but, don't want to unstep the mast this year. Would mounting the antenna on the stern pulpit transmit and receive any better than a handheld?

LakeSuperiorGeezer · #2 (**permalink**) 01-19-2011

No, since VHF is line of sight.

olson34 · #3 (**permalink**) 01-19-2011

I put a VHF antenna (ss 36" whip) on the top of the stern rail of our prior boat and it worked fine for the decade I owned it. Being a line-of-sight situation for range I occasionally did find that other boats were hard to tune in.
OTOH, no wiring in the mast or having to check on a distant antenna at the top.

Additionally, while it's not very likely that you will be dismasted, it is nice to have the stern antenna so that your radio is still working...
(Don't laugh -- the only time I was ever on a boat that lots its rig at sea, it actually did have a stern antenna and we were very glad to be able to let the USCG know. We returned to port under aux engine power, and no harm was done except for some large insurance company having to cough up $$$ for a whole new rig and some deck repairs...)

And, yes, it will reach out a lot better and your handheld with its little "rubber duck" antenna.

L

sailor50 · #4 (**permalink**) 01-19-2011

Be sure to buy a fiberglass (powerboat antenna) instead of a stainless whip for this application.

SlowButSteady · #5 (**permalink**) 01-19-2011

Since a fixed VHF can transmit at 25W (verses 5-6W for a handheld), and since the antenna is much larger, you should get better overall performance. Masts can, and do, fall (even a rail-mounted antenna can get damaged in various ways). Any fixed VHF should have an emergency antenna available for just such contingencies.

john1066 · #6 (**permalink**) 01-20-2011

Yes, a fixed set with a pulpit mounted VHF antenna will work better than a handheld.
But a masthead mounted antenna at, say, 40' above sea level will give you around 16nm (theoretically) to a similar boat; a deck level antenna, say 10', will give you 12nm to the same boat.
By the way, the formula is Distance = 1.4 x root of Height1 plus Height 2.
(The constant 1.4 is actually more than the true theoretical constant of 1.23 but in average atmospheric conditions the 1.4 is a better figure. Weird atmosheric conditions can give ranges of over 500nm, but you can't count on it!)
If you get a Metz they do a neat rail mount bracket that allows you to quickly remove the antenna, or move it to a less vulnerable location, when you're in dock.

celenoglu · #7 (**permalink**) 01-20-2011

A masthead antenna will be much better for transmission. If you wish to install it to the pushpit make sure you use a sailkboat antenna. Sailorboat transmit on a more ball like signal. Powerboat antennas transmit better on horizantal planes. You can transmit to better ranges with a sailing boat antenna when heeled.

Barquito · #8 (**permalink**) 01-20-2011

Thanks for the replies all. This would just be a temporary location for this season. Don't really want to buy two antennas (or antennae if you are a biologist), so, sounds like stern mount will work for now. I mostly need the radio for hailing bridges when I am almost under them.

Will probably just get the length of coax I will need to get to the top of the mast next year. This will also decrease my signal... ... maybe I should forget about the radio, and just yell at the bridge operator.

SlowButSteady · #9 (**permalink**) 01-20-2011

Quote:

Originally Posted by Barquito

... two antennas (or antennae if you are a biologist) ...

-- there ya go