WiFi Adaptors and Aerials

MedMan

MedMan

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WiFi in marinas is definitely on the increase, but there is an inherent problem for the those of us who are using laptop computers and a PC Card WiFi adaptor - the built-in aerial is at or below sea level. I did a search on these forums and found mention of "high gain 2.4MHz antennas and more powerful wireless cards" but I know nothing about these nor where to obtain them from.

What is the best type of adaptor/aerial combination to use with a laptop on board? What does it cost and where can I get it from?
 
I spoke to a berthing master at Haslar marina a couple of weeks ago on this subject. He lives aboard in that marina and suggested an independant WiFi receiver that dispatches bits and bytes to a laptop via a short cable into the conventional wired LAN port.

You can move the receiver around the cabin or put it outside under the sprayhood to get a better signal.
 
The easy way is to use a USB type receiver and aerial, so that the aerial can be placed higher up, or even outside the boat if necessary to acheive a good signal. PMCIA cards because of their size rarely have good aerials, and so tend not to be very clever in dealing with adverse reception conditions.

A good well placed aerial is paramount. A low gain receiver with a good aerial will always function better than a high gain receiver with a poor aerial which may pick up and amplify all kinds of spurious radio 'noise', which simply downgrades the signal.
 
I bought an 18dB yagi from:-

http://www.broadbandbuyer.co.uk/Shop/ShopSearch.asp?CategoryID=79&ShopGroupID=3&Alt=Yes

You would also need the 'wireless adapter' as the yagi is just a passive device with an SMA/N-Type connector. You would need an adapter which will accept an external antenna.

This setup gives a range of some miles (line of sight, 2.4GHz) but is highly directional. The short stub omni aerial that comes with the adapter should work in most marinas where WiFi is provided for the berth holders.

From my experience with Square Mile in the UK you will get nothing but frustration if you try to use your internal laptop WiFi card.
 
Re: WiFi Adapters and Aerials

The broadnbandbuyer prices seem obscene in comparison with this lot, click on Wireless Networking on the right of the home page. Their yagis are much cheaper, though for an aerial up a mast, I'd go for something that is not quite so directional.

If you are tempted to play, I found an US site that showed you how to but an "access point" (which you'll need anyway if the cable length is more than about 2m.) stuffed inside a tupperware box to make it waterproof, with some kitchen foil along the back to act as a reflector. Very low cost and highly effective. I'd try that approach first. Sorry but you'll have to Google yourself to find the site.

Minor grizzle, I posted this info: last month, so why did you not find it?? Are peeps getting a bit lazy in searching? I'm happy to help but sometimes it's a pain to repeat the same information.

Is it me??
 
Square Mile recommended the powered TCP/IP interfaced 'Airbridge Indoor' from Smartbridges
http://www.smartbridges.com/products/ab.asp
This has a much higher transmit power than a typical usb or PC card, and unless you are very close to one of the access points you will need something like this to get a reliable connection with reasonable speed.

I am in Haslar Marina and approx 300m from the two of the three connection points. With my Centrino the connection is variable, somedays it connects right away, on others it never manages it. With the Smartbridges airbridge on the boom with clear line of sight to the acces point I always get a connection.

I have been in the Travel Lodge in Hartelpool and got a good connection to the Marina which is at least 0.5 mile away and I always use this device when I am away in hotels as I get a much better and faster connction than when I just use the Centrino inbuilt wireless
 
Hi Medman,

see this item from D-Link:

http://www.dlink.com/products/?sec=0&pid=49

Plugs into USB with a wander lead so you can stick it on the coachroof/boom and work comfortably down below. Cost 60€'s. You can go further with wifi signal boosters but IMHO you start spending additional money when there's no need to

Steve
(Marina de Denia - using wlan wifi services)
 
Seems like a basic deficiency of the Service Provider. If they've gone to the expense of providing WiFi coverage in a Marina, you'd expect them to position and dimension their base station antennae so as to provide coverage that their prospective customers could actually use.
 
Medman - A few days ago, I posted info on the required kit and where to get it so have a seach. Drop me a pm if you can't find it. Thx
 
There need to be a level of distance compatability between transmit and receive. Whilst the provider may have ample coverage you as a user may not. If your wifi card has a range of 100 metres and the nearest service provider antenna is 200 metres away then you ain't going to connect.
 
Steve - that's the whole point of getting using a more powerful wireless card and a more sensitive antenna. Longer distances are feasable with the right kit.
 
Which is exactly why it's the Service Providers responsibility! This is no different to mobile phone companies who must use different techniques for different locations.
You don't see the users of WiFi hotspots at Airports, Starbucks in hotels etc etc walking around with high gain antennae connected to their laptops! This is because the SP makes sure that the coverage provided by their transmitters and the gain provided on the receiving antennae are adequate to provide a level of service that their customers can use!
 
Hi Dave,

so if my wifi card has a range of only 10metres then you are saying it is the service providers responsibility to place their antenna's every 20 metres?? There must be an onus on the user to have adequate kit to receive the signal - 400 metres is a generally accepted distance.


Steve
 
Damn, damn!

I've only just gone and bought an expensive new laptop (Tosh Sat Pro) specifically because it had a built-in wifi that I could use for marina connections. It seems I'm going to have to buy an external USB unit anyway, as I can only pick up a clear signal when out on deck. Not much fun this weather!

It looks like there is no way of rigging an external wifi ariel into a built-in card. Guess we'll need to wait for the next generation of PCs for this facility.
 
Hi,

If I get a --------The DWL-120 is Wi-Fi certified-------- I think I can see it will get me into the sytem from a marina with a 'hot spot' with the DWL sitting on the boom or coach roof!

What do I need to get into the system from another room in my house - I have ASDL = Broadband by Wanadoo.fr(I think) into my PC but use a laptop in other rooms and in the boat.......

What else do I need to be truly mobile with the laptop?

sorry if this is simplistic - trying to get my head round it!
 
Don\'t panic

You're still a winner:-

Get an "access point" as mentioned earlier, bung it in tupperware box up your mast, give it it's DC power - and hey presto you have a relay station which picks up the marina signal and rebroadcasts it to your laptop. No wires between the three.
 
Re: WiFi Adapters and Aerials

I hadn't realised how much I had overpaid - I didn't see those other suppliers when I googled back in October. I like the idea of the Tupperware box access point - might do that anyway. Thanks for the idea.

David
 
You need to wireless enable your pc. Add a wireless router, or simply plug a USB wireless access point into a usb port on your pc.

There's a bit of setting up to do, to get both of them to talk. This can be an absolute doddle with any luck, but if you encounter any problems, you are probably going to have to get someone that understands computers and networks to help you out.
 
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