can anyone recommend a decent stubby vhf antenna

[lanerboy]

i would like to change the vhf antenna on my boat from a long 2m antenna to as small as possible stubby version, reason is i could then get under weymouth bridge most the time without having to wait for a bridge lift

i know i can lower my antenna but where it is can be a pain unless i remove all the canopies which i dont want to do each time especially if the weather is poor

i also know it may not work as well but it will be fine for what i will be doing, also what sort of gain should i be looking for as a minimum standard

thanks

 

[VicS]

i would like to change the vhf antenna on my boat from a long 2m antenna to as small as possible stubby version, reason is i could then get under weymouth bridge most the time without having to wait for a bridge lift

i know i can lower my antenna but where it is can be a pain unless i remove all the canopies which i dont want to do each time especially if the weather is poor

i also know it may not work as well but it will be fine for what i will be doing, also what sort of gain should i be looking for as a minimum standard

thanks

This one ? http://www.mailspeedmarine.com/aerials-antennas-accessories/vtronix/heliflex-vhf-antenna102299.bhtml
http://www.force4.co.uk/482/Vtronix-Heliflex-VHF-Stub-Antenna-.html

or http://www.force4.co.uk/474/Banten-Regatta-Stub-Antenna.html

or http://www.force4.co.uk/6222/Shakespeare--Rubber-Duck--VHF-Antenna.html

 

[Whitelighter]

I see where your coming from, but do you actually want you VHF to be of any use?

With a short stubby ariel, you may as well bin it and use a hand held for all the good it will do you.

 

[LionsDen]

I see where your coming from, but do you actually want you VHF to be of any use?

With a short stubby ariel, you may as well bin it and use a hand held for all the good it will do you.

Totally agree with you Whitelighter - Shaun you need to keep it as is imho

 

[lanerboy]

I see where your coming from, but do you actually want you VHF to be of any use?

With a short stubby ariel, you may as well bin it and use a hand held for all the good it will do you.

i know what you mean but after looking around the marina yesterday there are quite a few motorboats with stubby antennas so they must be of some use for you to say i may as well throw it in the bin is a bit harsh. I did say i know it wont work as good as the antenna i have but i will only be tootling around the bay and will never be any further than a mile off shore so like i say it should be fine for what i need

i am meerly after some advise from more experienced members on which one to fit

thanks vics for your suggestions i have looked at your links and will wait to see if any other members have any other suggestions

 

[lanerboy]

Totally agree with you Whitelighter - Shaun you need to keep it as is imho

what about if i keep the antenna that i have but have it on a more horizontal fixing rather than vertical would this be better than a short stubby antenna or does it all depend on how high the antenna is

 

[kashurst]

nope it needs to be pretty vertical to work and the longer the better. Could you have it moved so its easy to access - say put it on the side of the radar arch a bit lower down?

 

[lanerboy]

nope it needs to be pretty vertical to work and the longer the better. Could you have it moved so its easy to access - say put it on the side of the radar arch a bit lower down?

yes i may have to do this instead then as at the moment is is right on the top of the radar arch and only accessible when the canopy is down

 

[LionsDen]

i know what you mean but after looking around the marina yesterday there are quite a few motorboats with stubby antennas so they must be of some use for you to say i may as well throw it in the bin is a bit harsh. I did say i know it wont work as good as the antenna i have but i will only be tootling around the bay and will never be any further than a mile off shore so like i say it should be fine for what i need

i am meerly after some advise from more experienced members on which one to fit

thanks vics for your suggestions i have looked at your links and will wait to see if any other members have any other suggestions

Hi Shaun please do not take this personally but it is irrelevent if you are only 1 mile from the shoreline when using a vhf as it is the distance you are from another vhf station that matters - This should have been explained to you when you took your vhf course recently. The longer the aerial and higher from the water line will make all the difference in you being able to transmit and receive vhf broadcasts

 

[Solitaire]

Your best bet is to use an antenna which is used on ribs. The ones previously shown are really for mounting on yacht masts. The V-Tronix is designed for ribs, they work well and I see no reason why you could not mount one on the radar arch. http://vtronix-antennas.com/antennashow.asp?cat=rib&show=yrr

 

[lanerboy]

thankyou david that is what i am after the antenna will still be higher than a rib antenna so should work fine then

 

[Salty John]

VHF radio range is always problematical on small power boats because range is subject to the height above sea level of the receiving and transmitting antennas. VHF antennas can’t ‘see’ much beyond the horizon.
The formula for range is 1.4 x √transmitter height in feet, plus 1.4 x √receiver height in feet. The answer is in nautical miles. Two power boats, each with an antenna 9’ above sea level, can communicate at 8.4 miles. (The theoretical multiplier is 1.23, not 1.4, but radio signals bend slightly and can see beyond the horizon by about 15%).
You can improve the situation slightly by using an antenna with a higher gain – those stubby antennas give no gain, 1m antennas are typically 3dbi gain, 2m ones are 6dbi gain, 6m ones are 9dbi gain. Gain is achieved by focusing the signal – the power output doesn’t change. If there is a great deal of movement of the antenna, such as you get on a boat, it’s better to have a lower gain because the less focused signal ensures that at least some of it is pointed at the horizon rather than at the sky or the water as the boat rolls and pitches. This problem is particularly bad when the antenna is atop a yacht mast so yachts don’t use more than a 3dbi gain antenna. (3dbi doubles the signal strength over 0dbi, but no matter how much gain you get it can’t push the signal beyond the theoretical limits explained above, but will give better reception within that range).
If you don’t need to communicate over long distances then you can get by with an antenna located low down – but as someone else said, you could also use a handheld. Leave your main antenna lowered until you intend going further off shore.
By the way, a phenomenon known as isotropic ducting occasionally allows vhf signals to be carried huge distances – many will have experienced this from time to time – but it isn’t predictable or reliable.

 

[lanerboy]

what i may do i think is get a hand held vhf and leave my fixed antenna in a lower position and just put it up if i am going further a field than weymouth bay this way i still have my long antenna if required but also have my hand held that i can use for the local blast out in the bay