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Growly
10-10-2004, 12:24 AM
Hi,

I just bought a nice 24 dBi parabolic grid antenna for a wifi connection to a mate's house - only trouble is I can't mount in because father is concerned that it will cause leaks and problems down the track.

My question is if it is really all that bad - is there a way that it can be done to avoid leaking?

Thanks

Rob99
10-10-2004, 12:26 AM
rtv

robsonde
10-10-2004, 12:44 AM
> My question is if it is really all that bad - is
> there a way that it can be done to avoid leaking?



leaking??
as in water getting in to the house??
or as in RF going places you dont want??

Growly
10-10-2004, 01:01 AM
Oh yeah - my bad.

Just for clarification - i mean water coming into the house and doing nasty things were we can or can't see.

That's water, not radio.

Rob99
10-10-2004, 01:21 AM
Do you have a TV mast that it could fit on.
Could you mount a tv mast (http://www.dse.co.nz/cgi-bin/dse.storefront/4167d74804866a76273fc0a87f990740/Product/View/L4642) from the guttering/barge board.

ps. Do you have a link for the antenna you have, for my own interest.

drcspy
10-10-2004, 07:51 AM
i used to work for a sky tv subcontractor outfit. the guys would mount th e dishe's by using 5" tech screws which screw into the beams under the roof iron......they use long buggers so that the dish wont move, even one degree out will stuff up the signal bigtime. anyway to stop leaks it's pretty simple .......BEFORE you screw in the tech screws put a generous dollop of silicon under the screw where you are gonna pierce the roof......make sure it's 'good' silicon you may need to ask the sales person what is the best type. That seals the hole so that rain dont get in they never got calls about leaks that i know of......

Growly
10-10-2004, 09:38 AM
Oh i see - so basically uh... right I'm confused, sorry, where do you put the Silicon? Around the hole? In the hole?

Oh, and I got a no name brand cheapo antenna: http://shop.borg.co.nz/product_info.php?cPath=24_21&products_id=92

Tom McB
10-10-2004, 09:39 AM
Yup, that's how it's done. When driving the long screws into the corrugated sheets choose the crests rather than the troughs where the rain water channels down.

drcspy
10-10-2004, 10:22 AM
put a BIG blob of silicon on where you are gonna drill then put the mount on then drill THROUGH the silicon andyes do it on the high parts not the troughs

Growly
10-10-2004, 10:22 AM
Corrugated? Our roof is tiled... Bit I guess the same principal applies...

tweak\'e
10-10-2004, 10:31 AM
what sort of tiles ?

you have to be very carefull with some types of tiles.

drcspy
10-10-2004, 10:38 AM
tiles different story you dont wanna break em.............try finding some wood even if it's at the end of the housem over the edge or even just use somewhere on the wall, so long as it's high enuf to get a line of sight with your friends house..........

Growly
10-10-2004, 10:54 AM
Well you see our house has two levels of roof - so i was thinking of mounting it on the wall outside, between the two levels.

Let me draw diagram:


________________
|
| The top roof ^
| <-- Wall. I was thinking mounting it here.... on this wall.
|
____________|

^^ Roof (this roof and the other roof are slanted, but i cant draw that :s)


I should really take a picture - wait till i get that USB cable...

Growly
10-10-2004, 10:55 AM
OK that didn't come out right - wait till I get that cable...

metla
10-10-2004, 11:19 AM
Buy a mast.

Tom McB
10-10-2004, 12:46 PM
Can't agree more.

With CI, you can at least see the line of fixing nails/screws which would then tell you where the beams underneath are. With tiles, I think they're held in place by concealed clips and you can't be sure.

Tiles being brittle, do break; this may not happen during your installation but might when the mast pulls on the tile that does not have much "give".

I can't see how you can screw into tiles the same way as you would on wood or iron without pre-drilling. You'd have to use a slightly bigger drill bit as well as the wrong size screwwould cause the tile to chip or crack.

Perhaps the easiest way would be the J-mast previously suggested. These come in different sizes to suit. To fix onto a concrete wall, use dynabolts or concrete nails to afix a short piece of H2 or H3 treated wood. Then use ordinary screws to hold the mast in place onto the wood.

tweak\'e
10-10-2004, 10:46 PM
there are many ways you can fix it to the roof or wall. if your tiles are metal then standard roof mount and stays is the easiest.

if concrete type tiles then its a simple matter of drilling with a 5/16th croncrete drill bit through the tile to the wood (lift the tile up to see the wood) and use 115mm tek scews. clay tiles...get a pro they are soft, touchy and exspencive to replace. the problem with tiles is there is always a risk of cracking them.

useing facia mount bracket is ok but you will need to stay it back to the roof otherwise the aerial will come off (and sometimes take the facia with it).

wall mount, the easiest here would be a saterlite dish wall mount. make sure its screwed into the studs (or structal concrete) and the outside cladding can handle the weight (ie don't fix it to plastic cladding)

if in doubt hire a professionall aerial installer. :-)

Raymondo
11-10-2004, 06:40 AM
Just a thought.
My last house had a high pitch tile roof so I put the TV antenna inside the roofspace. I did this because I had a reasonably strong signal (the transmitter was only a few miles away) and TV antennas do not add to the landscape.
Clay tiles do not shield the antenna. They may degrade the signal but in my case the reception was as good as I needed it. This was at least true for TV frequencies. I do not know how badly the tiles will attenuate the very much higher frequencies involved in the wifi link but if you are not working to extremes of distance it is qute possible that you could get away with an internally mounted dish.
If you already own the equipment it will only take a little effort to test it before you go to effort of doing an external mount.

drb1
11-10-2004, 07:19 AM
> Just a thought.
> My last house had a high pitch tile roof so I put the
> TV antenna inside the roofspace. I did this because I
> had a reasonably strong signal (the transmitter was
> only a few miles away) and TV antennas do not add to
> the landscape.


That is probably worth the effort of testing.

D.

R2x1
11-10-2004, 09:24 AM
>> Just a thought.
>>My last house had a high pitch tile roof so I put the
>> TV antenna inside the roofspace. I did this because I
>> had a reasonably strong signal (the transmitter was
>> only a few miles away) and TV antennas do not add to
>> the landscape.


>That is probably worth the effort of testing.

If they are metal tiles, no go. And if they are clay, it will save you the trouble of looking out the window to see if it's raining. Antennas are a black art, and with microwaves (above 1 GHz) there is a lot more black than art. Basically, if you want a low grade result, do a low grade job. Antennas that move in the wind are not much good at higher frequencies. For sealing, use lots of rtv under the bracket, and where the cable enters the building, ensure you put a "drip loop" (NOT a circle of politicians) where the cable comes down from the aerial, then up again (under shelter if possible) to go through the wall. This way rain drips off the bottom of the loop. Avoid sharp corners with the coaxial cable, and don't let it get squashed anywhere. If ANY water gets into a coax cable, it is no use as an antenna cable again, and useful coax at these frequencies is expensive.
Have fun.

Raymondo
11-10-2004, 11:22 AM
Growly ......one more thing if you intend to test an attic install.

If the construction of your house is such that you have wooden gable ends then, if possible, try to position the dish so that you are shooting through the weather boards rather than the concrete tiles.

And before you even get that far, set up the dish on a temporary stand and see if you can engineer the link through a window. If you can get it working before you have to worry about aerial location, you are more than half-way there.

Rob99
11-10-2004, 05:22 PM
You will need line of sight. Which means if you cant see the other antena the reception will be crap.

Growly
11-10-2004, 06:30 PM
Wow - so many ideas I haven't thought of -

THANKS GUYS!

I think I should further explain my situation - here are some photos. On the third story of my house, there is a study, in which a bunch of computers are located, with a view of the hill behind us. The house is tall and that helps alot because it means we can see the house I want to connect to.

Here is a view of the window at the back of the study that faces the hill behind and the proposed house:

http://sal.neoburn.net/imagef1/files/growly_study_back.jpg (apologies for poor photo)

Here is a close up of that back window and a bit of what you can see through it:

http://sal.neoburn.net/imagef1/files/growly_viewofthru.jpg

Here is a view of the house I intend to connect to - taken through the window, while standing in the study:

http://sal.neoburn.net/imagef1/files/growly_viewthruwindow.jpg

Right, now this is where it gets tricky. This is a view of the Window you were looking out of - only this picture was taken of said window from the outside:

http://sal.neoburn.net/imagef1/files/growly_atticandstudy.jpg

Importantly, this is why mounting it is dangerous, period:

http://sal.neoburn.net/imagef1/files/growly_dangerous.jpg

Finally, what the wall is made of:

http://sal.neoburn.net/imagef1/files/growly_wallmaterial.jpg

There it is - I think those are concrete tiles - they don't look metal. There is easy access to the roof from the otherside, but it's still steep --- but that's not a problem I guess. I will try and get a connection before I mount it.

Now I need to convince father.

Oh, and another question: If i mount it on the wooden apex of the roof, on the side, facing the proposed house, will that be be alright? It's a bit hard to see - but if you look at the picture of the house from the outside you'll see a red board around the guttering - that's what I mean but at the very top of the roof. The TV antenna is mounted on the same stuff at the other side, methinks.

Thanks very much.

Growly
11-10-2004, 06:31 PM
What's wrong, PressF1? Heehehe - sorry bout that, it messed the tags up, and I didn'y even use bold...

Growly
11-10-2004, 06:53 PM
Bad news - tiles are metal :'(

tweak\'e
11-10-2004, 08:10 PM
i would forget attic or wall mount.

a basic roof or facia mount (with stays of course) would be the easiest. simple enough to fix to the roof (metal tiles are no problem to put screws through to the timber underneath).

if you are doing it yourself a short hockey stick (facia mount) and short stays woud be best to minimize pole moment and not look to ugly. that way there is only 2 screws needed to go through the roof, less chance of water problem later on.

wiring can go into the atic space then into pc room.

don't fall off ! ! ! !

Raymondo
11-10-2004, 09:04 PM
I have to agree with Tweak'e - yopu're faced with two problems; an external mount and your father. Good Luck.

By the way - I looked at the photos and there is no reason that you cannot get a temp link going by firing through the window. Do that first and get the link working. Then, if you have problems when you go outside, you know it is due to installation hardware and nothing else.

Tom McB
11-10-2004, 11:28 PM
I've seen many SkyTV aerials mounted this way. Why don't you drive around and have a look.

Personally, I'd go for the fascia mount instead of the wall.

Link first, mast later is a very sensible suggestion. Then you can decide the where/how/who later.

Rob99
11-10-2004, 11:32 PM
You could make a very ugly wooden one and hang it out the window, just make sure it makes no damage to the window or the house, but is very very ugly. Might make your dad change his mind.

Growly
12-10-2004, 06:09 PM
THANKS GUYS!!!

Growly
12-10-2004, 06:18 PM
Well, yet another blow - the antenna is massive, @ 1m by 60cm - anyone still think there's a chance?

tweak\'e
12-10-2004, 08:02 PM
>Well, yet another blow - the antenna is massive, @ 1m by 60cm

so whats the problem with that ?

its only a mid size aerial ?:|

just stick the poles(+stays) in and install it ! ! !

Growly
12-10-2004, 09:40 PM
>so whats the problem with that ?

That's exactly what I wanted to hear :D

R2x1
12-10-2004, 10:45 PM
Doesn't the average " Russian Thermonuclear Intercontinental Ballistic Missile Silo" have an attached antenna farm?

Billy T
13-10-2004, 09:44 AM
For an alternative view:

It looks a little like you might be able to mount the antenna inside the attic. It depends on whether there is foil-backed building paper lining the inside of the walls, but if not, the path losses through the wall structure might not be significant over that small distance and especially with a hi gain antenna at each end.

Provided the attic area is not lined you should be able to see what the paper is like, and even if it is foil backed, the "Man in Charge" may accept removal of a small circle for the dish to fire through if you promise to replace it when the experiment is over.

Aligning the antenna might be a bit of a problem, but nothing that a compass, a builders level and a dose of patience won't sort out for you. A preliminary alignment in the room to get the approximate declination, a few minutes outside to get the compass bearing, then setting up the link so that you know it works before you take the antenna inside, and away you go.

Of course if the outer cladding is laid over wire mesh or such like, all bets are off.

Cheers

Billy 8-{)

Eric Richards
13-10-2004, 07:10 PM
It seems to me it was just a few weeks ago when I made a stand about the "Indoor Aerial" and got rubbished, It interesting to see that still no one from the PressF1 knows "Jack ****" about aerials.


You don't have the coax going from the shortest path from the roof to the hole in the wall or you will have water dripping down, inside your home. You have a "drip loop" that looks like a "j" from the outside, so the coax goes up from the loop to the hole in the wall, then the water will drip off the loop.
Also make sure the water will not go inside the coax, as I have heard once.

And before any one says a "Indoor Aerial" or rabbit ears is a aerial GO AND STUDY A AERIAL THEORY BOOK, and see if you can find any theory on them, like you will on a standard out side aerial.

Murray P
13-10-2004, 08:17 PM
Good advice on the drip loops guys, most aerial installations I see only prove that the installers know nothing about weathertightness or the materials they are working with.

Growly, avoid like the plague a roof mounting, especially on Decromastic tiles (they are Decromastic not a Gerrard tile) which are fixed to 40x50mm tile battens (not purlins as per iron) with probably one gun fired 90mm nail per truss which then could be up to 1200mm apart but most probably 900mm. Teck screws and a dollop of silicon will not do it (people should be barred from using the stuff unless they're licensed) and, as it looks like your looking into the Pauatahanui Inlet, probably from somewhere near the Crowsnest, the winds will be wicked at times.

Fascia mount if you must but, make sure your fixings are into solid by a good 50mm (not counting the 19mm of fascia) and be prepared to pop a gable brace in the roof space. Do use stays, fixed through the front edge of the tile not the top (the tile will simply crush down onto the batten if top mounted, providing a nice funnel for water and a loose mount), use a dab of silicon in the hole with a neoprene washer under the head of the tech screws. Stability will prove to be your friend for both the performance of the aerial and helping to prevent future water ingress.

If you mount on the wall, make sure your into solid, 7.5mm thick, textured fibre cement sheet will not hold anything. Again use stays, but this time at the fascia. Look the cable and seal the entry point against both weather and abrasion to the cable, circular PVC flange siliconed to the wall where the ebtry point will add to both.

Oh, BTW metal stays are better than guys to secure the lot against wind movement.

It's not the big gaping holes that let in the most water, it's the tiny little cracks, splits or delaminated silicon that gets it flowing. Most sealants don't perform well when exposed to the environment and less so when incorrectly applied.

Cheers Murray P

metla
13-10-2004, 09:06 PM
Alright,heres the skinny.

Mount it in the attic as per BillyT sugestion to remove any building paper,if it still no go then get a hammer,whack a hole through to the outside,Arial is garenteed to work,it will be far easier then getting on the roof........Plus,if your old boy don't like it just tell him to get his own house.

gees,the stunts me and my brothers used to pull would make a little hole in the wall look insignificant,Just remember kids...if you don't ask then they can't say no.

Billy T
13-10-2004, 10:58 PM
Steady on Eric, nobody is suggesting Growly use rabbit ears or even a half-wave dipole for his wireless link.

If you are worried about my suggestion to put his WiFi antenna dish inside their attic, don't be. A short range link with dish antennas will fire through a wall no problems at all. If WiFi signals couldn't get through walls, war-driving & war-chalking wouldn't have taken off.

As for the theory for balanced half-wave 300 ohm dipoles or unbalanced half-wave 75 ohm dipoles you need look no further than the ARRL or RSGB antenna handbooks, or any other good book on antenna theory. They don't call them rabbit ears of course, but the principles are exactly the same.

Rabbit ears may not be resonant in Band 1, but in Band 3 they can do a creditable job, if a little narrow in bandwidth for TV, and they are a much more tolerant on FM radio signals. For prime signal areas where choices for external antenns are limited by landlords etc they do just fine.

Don't get uptight about it, nobody is asking you to like them or even use them.

Cheers

Billy 8-{)

Growly
13-10-2004, 11:46 PM
>probably from somewhere near the Crowsnest

Mate, I am the Crowsnest. Well I live in it atleast...

Yeah thanks very much for the advice - very very very much! (Don't stop though).

My dad himself must be credited at this point, as he believes that in no way should I put it in the roof. This is probably because, although he hasn't told me, there is a large amount of reflective metal in that attic - none of which he will be willing for me to cut - so although feasible, as these are powerful antennae and it's only wood... the man will have none of it :'(

Therefore, if at all feasible, I am only left with the option of mounting it on a mast. At the other side of the house there is a TV mast with a TV antenna mounted on it in a similar fashion, unfortunately this is a) a bit too short and b) has trees within the line of sight.

It appears that Murray P has clearly outlined my Dad's fears. Unfortunately, I cannot see why the same labour cannot be put into mounting a mast for my precious antenna as had been put into mounting the now redundant TV antenna. from looking at it, it looks as if it is using a facia mount and two supporting poles.

Unfortunately this is also aided by the fact that some of the more overtly nosey neighbours will not rest at any opportunity to lay claim that my antenna is ------- ugly.

But screw them.

So let's review (so much technical non-computer related phrasing has confused me, and so if I got the wrong idea, please correct me):

I take said antenna and a mast. I get a facia plate. I stick mast to fash the plate, and i secure the mast with poles. While drilling I must be careful to to cause to many cracks. I must fill up with silicon (from in the attic, maybe?). I will tighten.

I take the cable and do some sort of loop (not quite sure where or how) so that the water drips off before going into the house. In doing so, I increase the signal loss (great.). I keep the cables dry, presumable with alot of electrical tape, or self-something tape.

I align it using diagrams, compass bearings and depression angles, which I figure out using some sort of tool (maybe one of those you point up at the sun and click, and then it tell you the angle? Like in maths?)

Then I plug it in and it works. (PLEASE)

Sound easy...




Hmmm - thanks again!




Oh, and

> Doesn't the average " Russian Thermonuclear Intercontinental Ballistic Missile Silo" have an attached antenna farm?

Only on Tuesdays.

Rob99
14-10-2004, 12:01 AM
Get a couple of quotes one from a builder and one from a TV areial person, go with the most expensive.
As you dont own the house just pass the bill on to the owner.

Murray P
14-10-2004, 12:36 AM
Hi Growly

Get yourself a heavy duty hocky stick mast from somewhere like Matchmaster (Strongline) 31 Bridge St, Lower Hutt 569 4916 or there's one in Motuhara Rd in Plimmerton 233 8194 (can you pinch the redundant TV one), they'll have all the correct fittings and bits and bobs.

Hang it off the house (make sure you have found a stud or dwang to attach it to) and brace with tubular metal stays off the fascia or if thats not high enough, mount it on the gable end fascia (the pointy one) and brace off the roof with stays. If you need to put the sealant on from inside the roof cavity your holes are way too deep or you've missed the solid stuff. Try not to use silicon or RTV where it is exposed to sunlight and the weather, use neoprene washers instead but do squirt some goo into the fixing holes and under brackets/mounts.

The drip loop is just a few 100mm of extra cable that sags below the entry point of the cable into the house. If you pop it up through the soffit lining (the eaves ceiling, if you like) and on into the roof cavity that will suffice as a loop, gives you less to flap around in the breeze as well.

Um! and Growly be carefull, got a scaffold or a harness? ;)

Cheers Murray P

Billy T
14-10-2004, 09:21 AM
> My dad himself must be credited at this point, as he
> believes that in no way should I put it in the roof.
> This is probably because, although he hasn't told me,
> there is a large amount of reflective metal in that
> attic - none of which he will be willing for me to
> cut - so although feasible, as these are powerful
> antennae and it's only wood... the man will
> have none of it :'(

LOL :^O Must be where he hides his stash, no wonder he doesn't want you in there. The "reflective metal" won't matter squat because it will be outside the bore-sight of the dish.

> I take the cable and do some sort of loop (not quite
> sure where or how) so that the water drips off before
> going into the house. In doing so, I increase the
> signal loss (great.).

No, it will have no effect on signal strength unles you kink or crush the cable.

> I keep the cables dry, presumable with alot of electrical tape, or self- something tape.

No, you don't need to tape the cable. Only joints or connections need taping to exclude water, but this install should have only one exterior connection and that should be inside an enclosure at the dish end anyway.

> I align it using diagrams, compass bearings and depression angles,
> which I figure out using some sort of tool (maybe one of those you
> point up at the sun and click, and then it tell you the angle?

Again no, you only need to do that sort of thing (minus the sun-gazing) if you are working blind inside the attic. Otherwise provided you can see the other dish you use your eyes and a bit of trial & error.

I'd go back to the attic idea, there is less chance of you stuffing up the roof or the exterior of the house.

Cheers

Billy 8-{)
You can always drill a 3mm hole to the outside
and look through that to help with dish alignment,
a squirt of silicon sealant closes it off afterwards and
it would be invisible from the ground.:D

When putting TV aerials inside lofts or attics
(pottery tiles only) I used to pop-up a tile and
check direction visually.

Pete O\'Neil
14-10-2004, 10:00 AM
Growly, how much coax cable do you intend to use? Anything more than a metre and you going to experience serious signal loss. You may need to consider mounting your AP close to the antenna to minimize the amount of cable required. The AP could them be connected to the rest of the network via cat5e and you could use PoE to power the AP.

Billy T
14-10-2004, 05:28 PM
That's a nice antenna Growly, I took a look at your link and found this quote:

Computech South Ltd has two of these products running as a network bridge from South Invercargill out to Lornevale which is 8.6KM.

You will have no trouble establishing a link over the short distance shown in your photos, even from inside the attic.

Re coax though, you haven't said what you will be using but unless it is absolute rubbish I can't agree with Pete's view that more than a metre will cause serious signal loss. If you have the right type for the job then 5-10 metres won't cause much grief at all. Just make sure you buy good low loss cable rated for 2.4 gHz use.

Cheers

Billy 8-{)

Growly
14-10-2004, 07:37 PM
Excellent!

Thanks so much everyone, hehehehe....

Right so now that my views are corrected - my options are a) mount on existing but slightly out of line of site TV antenna mast b) mount in secret attic c) get some chunky masts and secure tightly to roof, with aid of trampoline on ground and facia mounts.

Oh, and d) read a book on aerial theory.

As far as cable goes, I have some really expensive, ~$12 a metre type stuff lined up. Unfortunately, it may take a few metres before it gets to the er access point (which is infact a computer).

Hmmmmmmm.....

Oh and one last (well it's the last one untill I realise I have no idea what I'm doing and come crawling back for guidance) point ...

Will a 13dBm transmitter in a Wireless NIC be powerful enough? Or do I need a booster?

Pete O\'Neil
14-10-2004, 08:06 PM
Have a read of this (http://www.nzwireless.org/posts59-highlightlmr400.html) granted it might not be serious signal loss but with a 5m cable you loss around 2.5-3dBi, also taking into account that LMR400 is around $7-8 a meter the costs start to build up.

In my opinion you'd need around 5-10m of cable depending on the location of the antenna in relation to the computer room. Now using the above figures you can expect to loss 2.5-5dBi and expect to pay $35-70 for the cable.

Luckily Growly has one of the most powerful directional antenna readily avaliable in NZ, and is only transmitting over a relativly small distance. Now several people claiming to be antenna experts belive that the roof wont have any effect on the signal strength, im not a wifi expect but feel that the roof really should be taken into consideration.

You seem to be going about this in a very expensive way, if you were able to mount the antenna outside and mounted the AP as close as possible to the antenna you could have easily gotten away with the cheaper 19dBi parabolic grid antenna. You would have also only needed a small length of LMR400 again reducing costs.

Seeing as you are only tranmitting over a small distance you could have used a omni-directional antenna, it would have had the range and would allow for others to easily join your network (create a community wifi network). Your friend could have used a cheap cantenna or home made bi-quad to keep cost down.

Growly
14-10-2004, 08:47 PM
Thanks very much Pete, unfortunately I can't change my aerial now...

Nevertheless, the fact that it's so big just makes me feel like more of a man.

Believe it or not I actually originally intended to use a Cantenna - I even found the right can, had the holes marked, scrounged up money and bough a type N connector - all to realise I had no screws and no 12 gauge unshielded copper cable. Then the antenna I got went on special (down 25%) and I just went snap and bought it (had savings). Now I'm deadset on mounting it and pointing it out there, and I will save if I must and get good cable to do so. Understandably it is a powerful antenna, and there will be a slight effect on the signal through the roof, but I'm not experienced enough to make a judgement.

Anymore ideas are absolutely welcome. Infact I may start polishing shoes for all those who helped.

Having said all that, a big dirty grid antenna on the side of the house is extremely manly. (Well, more nerdy...)

Billy T
14-10-2004, 08:54 PM
> Now several people claiming to be antenna experts
> belive that the roof wont have any effect on the
> signal strength, im not a wifi expect but feel that
> the roof really should be taken into consideration.

Hi Pete

I would not advocate trying to establish a link through a metal roof. From the photos Growly has supplied it appears that he has a clear shot through the end gable.

You had better check that Growly, as the guy on site you are the only one who really knows what lies between your antenna and its target.

Cladding should be no problem so long as no metal or foil is involved, with reasonable power input and that antenna gain you should be able to establish a reliable link through trees or even an wooden building. I note from its specs that it is recommended for WiFi links inside buildings.

Cheers

Billy 8-{)

Raymondo
14-10-2004, 09:26 PM
Growly...you are getting a lot very good technical advice and I am sure that you will get the link to work. My last on this is simple. You don't have to resolve this problem before you do anything. You are the man on the ground. Have a go. You own everything so try what seems feasible - and simple.

Put the dish in the attic if it seems that it may possibly work and see what happens.. All it is going cost you is a little effort and time. If it doesn't work so what the hell. You have learned something. Now move on to the next step - whatever you want it to be. As long as each attempt doesn't involve a commitment you are not willing to make, either financial or structural, try it. There is nothing like a little experimenation to broaden the mind. Once upon a time that is what ham radio was all about.

When you have finallly found the spot where it will work, come back to this thread to get all the bells and whistles that will make it an A1 installation which may even earn some parental brownie points.

Rob99
14-10-2004, 10:42 PM
>you could have easily gotten away with the cheaper 19dBi parabolic grid antenna

He could have built a cantenna for about $10. Which is no bigger than two dog food tins end to end. And poked it out the window on the end of a stick when he wanted to link up.

Growly
16-10-2004, 12:18 AM
>He could have built a cantenna for about $10

I did... but couldn't find any 12 gauge copper wire...

Thanks very much for the advice everyone, greatly appreciated :D

Rob99
16-10-2004, 12:34 AM
I went to a scrap metal yard with my N Connector and tried a few bits of scrap copper wire, not sure if it the right gauge as I had to file the end just a little to jam it in the hole. But it works just fine. As long as it isnt to long(ie. dosent go over the half way) you cant go wrong.

Growly
16-10-2004, 07:00 PM
> I went to a scrap metal yard with my N Connector and tried a few bits of scrap copper wire

That's an excellent idea!