Rib Raider aerial

BogMonster · 27 February 2007, 19:15

Done a bit of a search and despite the fact they seem to fall to bits the Rib Raider aerials seem to be popular, I want something fairly small as otherwise I don't stand a hope of getting it posted here and arriving in one piece, according to one site they are only 57cm long which sounds good.

Anything else I should consider? The Raider is a bit under 50 quid from Mailspeed Marine. As I won't be refitting an A frame in the foreseeable future I will probably make a "mast" either from the transom or more likely behind the passenger jockey seat, so I don't want anything big and heavy as otherwise I'll need a bigger mast!

Ta

Stephen

al40 · 27 February 2007, 22:11

I think for a RIB the Raider is the best compromise. I did the same kind of research as you and came to the conclusion that a GRP whip will be more likely to break than the RAdier and the small stubby time of antenna would be useless on a RIB due to mounting height.

So far so good and almost all RIB's in the yard have Radiers fitted to them so they can't be too bad I guess.

V-Tronix claim the gain to be as good as a std whip (i have my doubts) but it does seem to work pretty well.

stevetheboat · 28 February 2007, 05:26

Whilst we do provide a lot of the V Tronix Raider antennas to RIB owners we have also found the Pacific 6106 a useful alternative, it has a variety of optional cable/mount kits and is particularly good if you have nowhere else to mount it but ontop of a console, for instance, it is extremely robust and very flexible - its also cheaper than the V Tronix

details can be found at the following web address

http://www.pacificaerials.co.nz/marine/p6106-SMPVHA.htm

jwalker · 28 February 2007, 11:08

It gives the gain as:

Gain 1.2dBi
"Marine Gain" 2.4dB

Anyone know what Marine Gain is?

JABS · 28 February 2007, 12:23

Don't go for an aerial with a high gain. The higher the gain, the 'flatter' the coverage. With a rib bouncing around, a low gain will give better coverage.

Whilst I haven't done it, I recently talked to a dealer who advocated fitting a stubby antenna inside the conslole. He felt this gave good performance and was secure and robust, hence less likely to let you down. Admittedley, he was in the Solent so range was probably not foremost in his mind.

I have fitted two antennas just in case! And it looks good!

The Garfish · 28 February 2007, 14:10

Quote:

Originally Posted by jwalker

Anyone know what Marine Gain is?

yus. itts wen a bote deeler fils iz pokkits wiv cassh arfter sellin yew a rowpy owld ribb

WOT MAREEN GAYN IZ FOR DAT NOBBUR WJ'S BENNYFIT

gaRf

jwalker · 28 February 2007, 15:42

So, I've got to be careful not to compare my apples to pears!

Thanks Garfie.

tim griffin · 28 February 2007, 18:00

Unity gain aerials used on yachts.The signal is radiated in a broad arc to compensate for the roll of the yacht.

High Gain Aerials are used on motor boats that remain more or less upright. The signal is radiated in a tight band at approx right angles to the antenna. Trouble is when it gets rough and they start to roll around and the antenna moves around abit you can get fluctuation on the radio signal an effect known as flutter.The Vtronic is I guess a hybrid suited for ribs .
When Jon Brooks comes along am sure he will answer in more detail.

Marine gain = what Garfie said

al40 · 28 February 2007, 20:16

Quote:

Originally Posted by JABS

Don't go for an aerial with a high gain. The higher the gain, the 'flatter' the coverage. With a rib bouncing around, a low gain will give better coverage.

Whilst I haven't done it, I recently talked to a dealer who advocated fitting a stubby antenna inside the conslole. He felt this gave good performance and was secure and robust, hence less likely to let you down. Admittedley, he was in the Solent so range was probably not foremost in his mind.

I have fitted two antennas just in case! And it looks good!

VHF is pretty much line of sight so surely you want the aerial as high as possible to avoid droput when you're in a wave trough?

The way I understand thw way the gain affects the waveform is that at 0db the antenna will radiate pretty much all directions. As gain increases, the radio waves travel more perpindicular to antenna. As has been already pointed out, powerboat antennas are usually long and high gain (9db) with very flat transmission. Yacht antennas are usually 3db and quite a bulbous tx field (RIB Antennas are pretty similar to yacht in terms of pattern but a yacht will have much higher range due tot he fact the antenna is on top of the mast)

The raider does seem to work well from what I've experienced so far.

BogMonster · 29 March 2007, 15:45

OK I now have my Rib Raider ready to fit on "something" (exact location yet to be decided)

Various people have suggested that these things have a tendency to fall to bits ... so whereabouts do they come loose and which bit falls over the blunt end? I might be able to do some preventative maintenance, at the wrong side of 60 quid inc postage, I don't want to be changing it too often

Thanks

Stephen

GED · 29 March 2007, 17:18

my rib raider kept snapping on the motorways something to do with vibration/frequency and 80mph

Neil Harvey · 29 March 2007, 17:47

my cable has come out of the bottom of the aeriial a couple of time, requiring a new brass bullet for the end. Vtronix were good in that they are sending me a replacement brass bullet to fit.

Also, Mine is currently loose as the nut that goes through the mount bracket is very stiff and needs doing up with a spanner. Makes removing for the motorway etc a bit of a pain.

Biggles · 29 March 2007, 19:44

Quote:

Originally Posted by BogMonster

OK I now have my Rib Raider ready to fit on "something" (exact location yet to be decided)

Various people have suggested that these things have a tendency to fall to bits ... so whereabouts do they come loose and which bit falls over the blunt end? I might be able to do some preventative maintenance, at the wrong side of 60 quid inc postage, I don't want to be changing it too often

Thanks

Stephen

Steve,

I am at the moment on the Mark 1 anti antenna losing mod. It consists of wrapping some fishing line round the base of the antenna and also the curly bit of the aerial. I lost the antenna last time. Hopefully if aerial does come out then at least I should find it dangling off the A Frame.

BogMonster · 29 March 2007, 19:49

Quote:

Originally Posted by Biggles

Steve,

I am at the moment on the Mark 1 anti antenna losing mod. It consists of wrapping some fishing line round the base of the antenna and also the curly bit of the aerial. I lost the antenna last time. Hopefully if aerial does come out then at least I should find it dangling off the A Frame.

Biggles,

Whereabouts did yours part company - at the base or where the springy bit goes into the more rigid lower section?

Biggles · 29 March 2007, 20:20

I lost the metal antenna bit. If you look at where the antenna goes in to the egg cup sized base there is a small plastic nut you can tighten that grips the antenna. I think mine just came loose and the antenna fell out. I think it would be hard to lose the base as its quite substantial.

wavelength · 09 May 2007, 18:26

Quote:

the antenna fell out

and so did mine in on the N Wales cruise - B*%^£* !!!! --Lots of pics with it in place - followed by more pics later in the day without it

So it looks like the fishing line hi tech mod for the next on eh! I have to keep taking the antenna bit out so that it goes under the garage door,will have to loop the fishing line over the masthead light each time I suppose- then the one day I forget guess what will happen

havener · 10 May 2007, 15:32

Quote:

Originally Posted by wavelength

and so did mine in on the N Wales cruise - B*%^£* !!!! --Lots of pics with it in place - followed by more pics later in the day without it

So it looks like the fishing line hi tech mod for the next on eh! I have to keep taking the antenna bit out so that it goes under the garage door,will have to loop the fishing line over the masthead light each time I suppose- then the one day I forget guess what will happen

Consider yourself lucky Dave - I know one station where the crew did that with the folding upper radar array on a Mersey lifeboat.....