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gusi
2006-11-17, 09:01
My PC and SB are on opposite sides of the house.

Typically I get 50% signal strength, but often on humid days it drops to 15-30% Once the signal gets around 20% the SB starts to drop out.

I placed the SB and wireless router as high as possible and this has made some difference.

Is there anything else I can do? I saw what looked like directional antennas in a computer shop several years ago but didn't take much notice of them. Do such antennas exists and are they more efficient in that direction.

Buying a hub with a stronger transmitter would be one option but the current hub is not obsolete yet.

I also have an older wireless access point I could place halfway but am not looking forward to its configuration.

Buying a huge air co unit to keep the house dry is not an option. ;-)

cheers
Gus

Mark Lanctot
2006-11-17, 09:22
You can gain a bit of signal by changing channels away from crowded ones.

This and more here: http://wiki.slimdevices.com/index.cgi?NetworkProblemsSecondGuide

High-gain and directional antennae do exist and are apparently very effective - also cheaper than buying a new router.

Buying a new router may not solve your issue. They're usually not rated in terms of signal strength. However, the newer MIMO routers may help out - in particular, the Ruckus Wireless routers are optimized for just this sort of application (media streaming) and are recommended by Slim Devices.

If you have a Linksys WRT54G, you can install 3rd party firmware which will allow you to adjust the transmitter signal strength. But as you do this, the radio module gets hotter and may fail prematurely. It's considered much safer and more effective to get a high-gain antenna. It also won't void your router warranty, if it's still under warranty.

azinck3
2006-11-17, 09:23
Buying a hub with a stronger transmitter would be one option but the current hub is not obsolete yet.

Not really tracking your logic here. Seems like if your current devices aren't working for you and there are devices that exist that would fix your problem for a reasonable price, then perhaps you should consider an upgrade. The Ruckus access points/routers have gotten rave reviews for range. 802.11n access points would probably also be a good solution.

Another option: Homeplug adapters

Not sure how well the antenna solution would work.

SuperQ
2006-11-17, 09:29
Is there anything else I can do?

cheers
Gus

Yes, first tell us what kind of AP you use. And what floors you have the AP on and the squeezebox on. Wifi is most blocked by walls, so moving the AP to eliminate walls would help.

The next thing is try changing between channels 1, 6, and 11. If you have a wifi scanner like netstumbler, or iwlist on linux, you can check to see what other APs are around..

The third thing you can do is change the orientation of the antennas on your AP, or add higher gain antennas. However, if you add higher gain antennas, and you have multiple floors, it can make things worse on other floors. (higher gain flatten the RF pattern) Or if your AP is on one end of the house, you could use a directional panel antenna.

http://www.fab-corp.com/product.php?productid=1438&cat=255&page=1

Of course, you'll need a pigtail cable that is compatible with your AP.

Mark Lanctot
2006-11-17, 09:34
Not sure how well the antenna solution would work.

I haven't had to use this as my signal strength has never been bad enough, but all the anecdotal evidence suggests it's very effective. In fact, SuperQ's post regarding the RF pattern is the first negative I've heard.

Check out this very recent post, for example:

http://forums.slimdevices.com/showpost.php?p=155506

SuperQ
2006-11-17, 10:01
I haven't had to use this as my signal strength has never been bad enough, but all the anecdotal evidence suggests it's very effective. In fact, SuperQ's post regarding the RF pattern is the first negative I've heard.

Check out this very recent post, for example:

http://forums.slimdevices.com/showpost.php?p=155506

Antennas don't add signal, they act like a lens and just focus the signal. just like a zoom lens on a camera. Most APs use omnidirectional antennas. when pointed up, think of this like standing in one spot with a camera, and spinning around in a circle. A crappy 2dbi antenna is like using a fisheye.. you will see everything in the room, but not very well. If you use 5dbi, it's more like a 35mm lens.. not bad, but you're not going to get details on the far walls. 9dbi is more like a 70-100mm lens.. maybe a bit too much zoom for using inside.

It mostly depends on how much gain you're adding. like the post you linked said.. the APs come with very crappy 2dbi antennas.. upgrading to 5dbi isn't too much of a problem because it is still a very wide signal. if you go up to 9dbi, you start to flatten out so that if you make both of the AP's antennas vertical, you may have floor to floor problems, but it won't be too bad. With a 15dbi omni (I've used for outdoor links) you're talking maybe 10 degree signal width along the antenna plane, but you can connect a mile away with a good directional dish.

SteveT
2006-11-17, 10:38
Hi Gusi,
I had a similar problem and bought one of these to go on my pc's pci card."http://www.maplin.co.uk/Module.aspx?ModuleNo=38211&&source=14&doy=search"
It's only a 5dbi gain but was very effective at the price.
Maybe you need 2.......one for the Router and one for the PC.
Try one first and if it doesn't work take it back to the shop.
Good luck.

gusi
2006-11-17, 10:41
Thanks for the advice everyone.

I live in a single story brick and tile duplex.

I'll check out the other channels and also the special antennae. Perhaps the neighbours have a cordless phone.

Since I don't have an upstairs I can also try a higher gain antenna.

I have been a unix nut since the 80s so I'll give iwlist a go as well.

gusi
2006-11-17, 10:51
Thanks Steve I'll check that one out too. The antennas I saw years ago looked like little radar dishes. Except that they didn't rotate continuously.

To clarify my setup:

The PC with router/AP are in the study, the SB is in the living room on the other side of the house.

It is a netgear DG834. When prices drop I'll probably get something with more ports, 802.11n and voip but for now it works fine for me.

I could eliminate the walls by putting it in the ceiling space but then I might as well pull a cable.

I also have a retired d-link 802.11g router/AP which I could place in the kitchen half way. But as I suspect that this may not be that easy to setup as a relay, I'll play around with the channels and antennas first.

Mark Lanctot
2006-11-17, 11:21
I also have a retired d-link 802.11g router/AP which I could place in the kitchen half way. But as I suspect that this may not be that easy to setup as a relay, I'll play around with the channels and antennas first.

Yes, this is known as WDS (Wireless Distribution System):

http://en.wikipedia.org/wiki/Wireless_Distribution_System

While it can increase effective signal strength, bandwidth will drop:


It should be noted, however, that throughput in this method is inversely proportional to the number of "hops", as all traffic uses the same channel. For example, client traffic going through one relay station before it reaches the main access point will see at most half the maximum throughput that a directly connected client would experience.

But you should still have enough capacity for WAV and FLAC.

It's apparently pretty tricky to implement, equipment from different manufacturers doesn't work that well together. Even equipment from the same manufacturer may be tricky to set up. For one thing, many router firmwares don't even have the option.

azinck3
2006-11-17, 11:26
Yes, this is known as WDS (Wireless Distribution System):

http://en.wikipedia.org/wiki/Wireless_Distribution_System

While it can increase effective signal strength, bandwidth will drop:



But you should still have enough capacity for WAV and FLAC.

It's apparently pretty tricky to implement, equipment from different manufacturers doesn't work that well together. Even equipment from the same manufacturer may be tricky to set up. For one thing, many router firmwares don't even have the option.

I use WDS (on dd-wrt routers) to cover the three floors of my house and it works quite well.

gusi
2006-11-17, 11:39
It's apparently pretty tricky to implement, equipment from different manufacturers doesn't work that well together. Even equipment from the same manufacturer may be tricky to set up. For one thing, many router firmwares don't even have the option.

Yes I was afraid of that Mark. Before the netgear router/AP all in one solution I used a webexcel router/hub together with the d-link AP/hub. It was a pain to set up, required numerous d-link firmware upgrades quite a few goes at getting the NAT and dhcp schemes right and even then it needed a reboot every couple of days. And that was with the ethernet ports connected together. I can imagine the SB latching on the correct signal and sticking with it to be much trickier.

Mark Lanctot
2006-11-17, 11:50
Yes I was afraid of that Mark. Before the netgear router/AP all in one solution I used a webexcel router/hub together with the d-link AP/hub. It was a pain to set up, required numerous d-link firmware upgrades quite a few goes at getting the NAT and dhcp schemes right and even then it needed a reboot every couple of days. And that was with the ethernet ports connected together. I can imagine the SB latching on the correct signal and sticking with it to be much trickier.

It would be more getting the Netgear and D-Link routers talking to each other for WDS. The Squeezebox wouldn't care much.

The DD-WRT aznick3 mentions is one of those 3rd party firmwares for the Linksys WRT54G. I use it, it's excellent. It definitely can operate in WDS, but it's very advanced. I didn't use the original Linksys firmware for long so I don't know if the factory firmware supported it - I doubt it.

So your Netgear and D-Link routers would both have to have a WDS option in the firmware. There are no 3rd party firmwares for these routers, so if it's not in the factory firmware, you're out of luck here.

I have a retired SMC router that I'd like to use for this, but it doesn't have the option in the firmware and one hop from my Linksys direct to my SB2/Transporter and laptop works OK, so I don't need it.

gusi
2006-11-17, 12:03
I just had a quick squiz in the netgear and I didn't see anything about WDS. Anyway antennae and channel are the other options.

One of my friends uses a linksys so I'll keep the third party firmware in mind. His issue was not so much reaching the whole apartment as keeping the neighbours out. They had up to 10 'pirates' at a time before we set up his encryption.

Mark Lanctot
2006-11-17, 12:18
I just had a quick squiz in the netgear and I didn't see anything about WDS. Anyway antennae and channel are the other options.

They may call it something else - WDS is the official IEEE name, but they may call it "repeater" mode or something.


One of my friends uses a linksys so I'll keep the third party firmware in mind. His issue was not so much reaching the whole apartment as keeping the neighbours out. They had up to 10 'pirates' at a time before we set up his encryption.

Getting OT but seeing as you're the original poster you can take it in any direction you want. WPA works very well for this - WEP is practically useless but will keep out casual/accidental connections. The Squeezebox supports WPA2/AES which has even stronger encryption than WPA, not that WPA encryption has been broken. I've had WPA2/AES working effortlessly on the Squeezebox for the past 6 months at least.

The only attack for WPA is a dictionary attack, so make sure your passphrase can't be found in a dictionary. Use poor spelling, numbers and odd punctuation. :-) The length of the passphrase determines the "depth" of encryption so use a 63-character passphrase for 256-bit encryption. Entering 63 characters, including numbers and punctuation, on a Squeezebox using the remote is pretty slow though. Thankfully you only have to do it once.

azinck3
2006-11-17, 12:27
One of my friends uses a linksys so I'll keep the third party firmware in mind.

It's not only the wrt54g/gl models that support dd-wrt. There are actually a lot of routers on which it can be installed. I personally use Buffalo units because they're significantly cheaper than the Linksys models. Check out the dd-wrt web page for a full listing of supported hardware.

radish
2006-11-17, 12:29
You really don't need to use a 63 character key, that's just making life hard for yourself :) A 10 character randomly-generated string is way more than adequate.

http://blogs.zdnet.com/Ou/?p=127

Mark Lanctot
2006-11-17, 12:33
You really don't need to use a 63 character key, that's just making life hard for yourself :) A 10 character randomly-generated string is way more than adequate.

http://blogs.zdnet.com/Ou/?p=127

Cool. Then again, I'm pretty anal about things. ;-)

gusi
2006-11-17, 22:46
We used a 26 byte WEP key. I didn't realise that it was so easy to crack.

It is also easy to see who is connected and since we installed WEP we didn't see any unknown connections.

He lives in a Singapore apartment block and someone in Sgp is about to be made an example of for wifi free loading. http://www.theregister.co.uk/2006/11/13/singapore_teen_war_driving_charges/

I'll have to change my own encryption when I get a bigger antenna.