Best RIB VHF aerial for long range?

[Pikey Dave]

When I bought my Icom radio at the LBS, I asked the blokes on the Icom stand which antennas they recommended & they said Procomm. I'd never heard of them so I did my homework & eventually bought a pair, one for the VHF & the other for the AIS. They are well engineered & well made. I like the fact that unlike the Glomex range, the cable connection is a proper soldered N type plug rather than the dodgy (IMHO) Solderless type. The base is sturdy. The only caveat is that Icom distribute Procomm, so they are naturally going to recommend them, the flip side to that is, I wouldn't expect Icom to promote cr4p.
I've had GRP Vtronix in the past & had them break, Glomex seem to be at the cheaper end & the last time I looked, Pacific were difficult to get hold of, but that may have changed. The Metz seem to be good quality & have a loyal following, they're just a bit "whippy" for my liking.

[ShinyShoe]

Originally Posted by Erin

Dependent on atmospheric conditions I can receive VHF transmissions from 60 miles away (south coast from Alderney) and also have no problem getting my traffic reports through to the CG when up to 35 miles out.

Is that 60miles a shore station on a tall mast on a tall cliff transmitting at ? 100W ? Or someone on a RIB with a 25W and an aerial on an A-Frame? It very much depends who and why you need to call them.

[Pikey Dave]

Originally Posted by ShinyShoe

Is that 60miles a shore station on a tall mast on a tall cliff transmitting at ? 100W ? Or someone on a RIB with a 25W and an aerial on an A-Frame? It very much depends who and why you need to call them.

When we're in Northern France we regularly communicate with Solent CG 90 miles away. We might be skip bouncing (which I doubt as it's constant in all weathers), but comms are loud & clear in both directions.

[ShinyShoe]

I think thats perfectly feasible. The solent mast is tall and on a cliff top. We know you can get 5W to reach outerspace as PLBs transmit at 5W and talk to satellites. The issue is talking to another station at ground level where the signal doesn't bend with the earth.

[Erin]

Originally Posted by ShinyShoe

Is that 60miles a shore station on a tall mast on a tall cliff transmitting at ? 100W ? Or someone on a RIB with a 25W and an aerial on an A-Frame? It very much depends who and why you need to call them.

IIRC it was Brixham that I heard last time I listened. Having said that, I can call Jersey CG from Alderney on 1w and communicate with them no problem and that's 30nm. Admittedly they've got a big aerial but surely the only time we'd want such long distance communication is when trying to talk to the CG. Ship to ship would typically be much shorter distances.

[Salty John]

Height above sea level trumps other issues for range. Range in nm is 1.4 x sq.rt. of your height above sea level in ft plus 1.4 x sq.rt. of his height above sea level in ft.
(I'm sure there's an easier way to write that!)
The constant 1.4 takes into account the slight bending of the radio waves to "see" over the horizon a little way.

The taller the antenna whip the more focused the radiation pattern; this is not necessarily a good thing on an unstable platform like a boat - the signal will spend a lot of time pointing at the sea and sky rather than the horizon. So, for example, a 1m whip on a 1m extension pole is better than a 2m whip.

The cg, as others have said, have powerful transmitters mounted very high above sea level and have, therefore, a large horizon distance. Two RIBs in heavy seas are probably the worst case scenario - 1m whips mounted as high as possible gives the best range between them.

[boristhebold]

Originally Posted by Mollers

I dumped a Rib Raider for a Shakespeare 1.2m GRP. The improvement was massive and it doesn't look as if it's likely to break.

Me too, placed a 1.2M Shakespeare GRP aerial on a stainless folding bracket on top of my A Frame to the port side of the A Frame Bracket, I used gold plated connections to a connector in the aft part of my boat, the rest of aerial wire from that connector to the VHF unit in console.

I found the improvement was also significant from my previous aerials which were the wire whip types. I am very often picking up French VHF traffic from south coast, when doing a radio check im always heard loud and clear and pick up is good. In fact when I first fitted it on my driveway near Ringwood I could pick up the coastguard traffic. !

The folding aerial bracket allows me to fold the aerial back towards the back of the boat about an inch away from top of outboard casing just to the port side which allows more room in the dry stack racks above and allows me to have it folded part of the way down when going under Poole Bridge and the Twin Sales Bridge even at very high tide.

Having the connector in the aft is just in case I do need to replace the Aerial I wont need to replace the entire length of aerial cable through the boat which is a pain to pull stuff through due to all the other cables etc.

So yes I would recommend a shakespear 1.2M.

[PaulB2180]

Thanks all. Erin I would appreciate a look at your boat in the New Year, mine is in need of some updating and yours sounds as though it is well sorted.

My A frame is crying out for a radar reflector and a solar panel as well, so a new VHF antenna is just the thin end of an expensive wedge!

Cheers

[Pikey Dave]

Originally Posted by PaulB2180

........is just the thin end of an expensive wedge!

Cheers

Aye! especially when you add the VAT on

[PaulB2180]

Originally Posted by Pikey Dave

Aye! especially when you add the VAT on

Have no fear. We have sales tax and import costs which "magically" often take the price beyond the UK price inc VAT.

Ironically buy most of my fishing gear from Scotland...(Glasgow Sea Angling).

[9D280]

FWIW I have both a Raider and a 1.2m shakespere 'glass whip. It;s a long story involving the mounts and a garage door, but ignoring the proactialities of my A- frame, I have both, patchable insiode the console.

Now, I grant you I donlt do the sort of Long distance some on here do, but about 5 years ago there was a variation of this thread which if memory serves went on to show that the older models of Raider had what some might describe as a fundamental water ingress issue. Mine os one of the newer design, and even after smacking the top of the garage door a good few times (hence the two of them - the folding bracket was cheaper to buy in a long bag with a whip antenna I rthen opicked up another folding mount...but I digress.....

Bottom line- Reception difference? - immesurable. TX difference - not had to repeat anything more with one that 't'other.

I think I have the Whip hooked up at the moment - the difference is so great I'll need to go look at the patch panel to see which one is in use!


I do feel we can get overly deep on arguing the theory in here sometimes.....

[office888]

Range is dictated by:
1.) Antenna height
2.) Antenna type (Stacked collinear, 5/8 wave, 1/4 wave, 14-element yagi, etc)
3.) Wattage

This goes both ways for the TX and RX station.

[Erin]

Originally Posted by PaulB2180

Thanks all. Erin I would appreciate a look at your boat in the New Year, mine is in need of some updating and yours sounds as though it is well sorted.

Sure. Will be back in the water at the beginning of May. A bit difficult to let you see much beforehand as she's all wrapped up for winter now but can probably dig a couple of photos out if it would help.

[PaulB2180]

No rush. Merry Xmas.