Network bodge question

[tony sayer]

Not really as if you were measuring the actual power you'd go for a direct connection to the transmitter and then calculate the aerial gain by such as NEC modelling..

Well we have to be somewhat careful as this is sometimes expressed as dBi decibels relative to an Isotropic radiator thats to say a perfect radiating point source thats a theoretical concept as it can't happen anyway..

dBd decibels relative to a Di-pole which is a definable real world concept usually taken as 2.1 dB better than an isotrope..

Then there is ERP Effective Radiated Power in a nutshell thats what's radiated whatever you do to increase the output of the transmitter source you have usually done by focusing the available energy into a narrow beam like a car headlight it does NOT increase the overall amount of energy just defines that way its used...

If that is what you want to do then yes..

Not Ommni, more diversity..

[tony sayer]

Indeed thats the case there is very little bandwidth available at 2.4 Ghz and its a mighty crowded part of the spectrum and thats the real reason why most all people have trouble extending range and coverage.

It's interferer's from next door and next to that etc that are the main real world problem:(...

[tony sayer]

In article , Johnny B Good scribeth thus

Well if the transmission path is there then yes you can do that. What you make your aerial out of is immaterial, course you don't really want a chicken mesh one when its up a bloody mountain somewhere, you need ones that are heated or have radomes to stop Ice formation etc.

We have used pretty standard ubiquity equipment and have had ranges of up to 42 KM out in the flat lands of east Anglia but at that sort of range the likelihood of interference is the limiting factor....

[John Rumm]

I would say your chances lay somewhere between "slim" and "fat"...

I needed to use a "high power" version of the homeplugs to get reasonable consistency in my workshop. Alas I am not sure if you can still get those. (cable distance probably similar - and going through a chain of several CUs)

[John Rumm]

You could use a pair of wireless bridging units - 20m is child's play for them. I have used them in the past to link customers offices where they have one office either side of a main road. Broadband and telecoms come into one, and then all data and phone (via IP Phones) is bridged over the road. Seems to work very well.

[Alan Braggins]

Google says Ofcom say it is EIRP.

But if you are a neighbour in the same direction as and beyond the intended target, having all the energy pointed in your direction is a less good thing.

If it's a really tight beam with line of sight for 1km, that's unlikely, but for "pointed down the garden towards the shed", it may be more of a problem.

[spuorgelgoog]

I think so.

You could try SLIP over RS232 if you want to reduce the Ethernet packet overhead :-)

Owain

[Bill Wright]

I'm talking about professionally installed systems intended to cover a wide area, like a caravan site or marina.

Bill

[Mike Tomlinson]

En el artículo , Martin Brown escribió:

connect the chicken wire to your router's antenna output?

(Just joking :)

[Chris Bartram]

Yeah, I'd just try it. I've run ethernet over phone cabling OK when desperate.

[Chris Bartram]

Yep. Exactly that was done in my last job for an external, line-of-sight link. It worked OK.

[Harry Bloomfield]

The Natural Philosopher presented the following explanation :

1km is fairly easy to do.

[Dave Liquorice]

I'd give it a go but not spend much time on it.

Bloomin awful things bung 'em in the bin.

Shouldn't be. What's in the way between the workshop and WiFi unit in the house? If might just be a case of moving the WiFi in the house to a place where it is less obscured by walls enroute to the workshop.

What do you need on the network at the workshop end? Just a single PC or other kits as well? Single PC USB WiFi dongle on an USB extension cable in a window facing the WiFi in the house. Multiple devices a small switch with one port connected to a WiFi device that can act as a client. Maybe the Maginon plugin dual-band WiFi repeator/client/access point that Aldi have for £14. Think about where this kit is sited though, the more "in the clear" you can have either end the better.

Or ask how much Mr Sayer would want for a couple of his surplus EnGenius link kit.

[ChrisK]

Also don't forget the water absorption - that is partly why it was freed for unlicenced use (and the same reason that it is shared with microwave ovens). It is a bit iffy outdoors in damp conditions.

It seems that a lot of the record distance attempts take place in various US deserts.

Is 5GHz any better in rain and mist?

Chris K

[tony sayer]

We have had one 5.8 Ghz link over a 10.6 mile path on the go since 2005 and in that time its been down due to,

An odd type of "layered" fog;!.

Wrong sort of snow.

Poor Alvarion equipment! Now replaced with Ubiquity.

Thats it...

It does work fine in heavy rain and mist the fog was some sort of inversion thing, only happened the once. The snow was very horizontal snow that was literally coming in sideways, some must have built up a small area that stuck and the snow rapidly built up and that clobbered it.

However the bit of internal heat generated by the unit melted it after a while and the link restored and all was well:).

Have just had the once where another link was received from many miles away and that happened one night, no odd met circumstances were in evidence.

As to long range 2.4 Ghz don't bother with it too much interference and very overcrowded....

[Dave Liquorice]

Microwave ovens work more on brute force than molecular resonance.

There was very little if any problem with the 2.4 GHz WiFi links used for the local wireless broadband network backbone links installed in the early 2000's. These links were (still are but on 5 GHz now) anthing from 1/2 a mile to 15 miles. The longer ones used 18" dishes each end. Bear in mind that these links will frequently be in cloud with rain at 1/2" per hour, not loss of links. If it really chucks it down we might get 2"/hour that can kill 'em and DSAT but that sort of rate only lasts 5 or 10 minutes.

Icing would be a problem on Great Dunn Fell, we did tell 'em that they ought to provide heated kit but did they listen... just like they listened to us telling them that any wind turbine to provide power on Mount Hooley will have to be rated up to well over 120 mph to stand a chance of surviving. It lasted about 3 months...

Couldn't get up to Great Dunn Fell (nearly 2,800') to see the icing but I've seen Hartside (2,000) under a couple of inches of solid ice and our DSAT dish (1,400') has collected >1/2" on several occasions which kills the satellite signal, requireing dish being whacked by broom handle to get rid of it.

In the crowded south or population centers (village centers up) certainly but not for many of the links up here.

[rick]

Not sue what homeplug units are like .... but Power-Line converters should work OK.

[tony sayer]

Yes quite a few aerials are made with inbuilt heating elements for exposed adverse weather locations

;!...

I think that ones used by Arqiva to supply terrestrial Tx's are either heated or have some odd coating on..

That place Dave sometimes sounds like another planet the way you describe it;)....

Despite being on the English mainland!.....

[Dave Liquorice]

Mount Hooley has nothing between it and Great Dunn Fell. Great Dunn Fell is the windiest place in England if not the UK. Sustained wind speeds over 70 mph are fairly common. It's not what we would consider windy today, but up on GDF it's blowing an F7 Near Gale low 30's mph. Gusts are nearly 40 mph but it's not windy.

interference

Another world certainly. Even within a couple of miles and a few hundred feet lower you can go from near blizzard conditions and several inches of accumulated snow to rain and no snow. Go down to Hexham/Carlisle/Penrith and it's one jumper warmer down there. If there isn't at least one day/winter when the roads in/out aren't closed by snow we haven't had a winter. A "bad" winter will have some roads closed for weeks and even getting the main ones open can take days.

Some don't like it but "Englands Last Wilderness" is pretty accurate. People think Dartmoor is big, bleak and remote. You can place six Dartmoors in a ring around here without covering any major population center. Head in several directions and once past the local population you can go for around 10 miles and have nothing but open fell, no sign of recent (within the last 50 to 100 years) human activity at all.