I bought some aluminium tube to make antennas

[doug3030]

We are going camping with a group of friends over Easter, to a place we have been before and know that it is out of range for mobile phones and internet.

I decided that before we go, I would build a decent antenna or two so that we can get our internet to work so everyone can check their emails etc and make phone calls if needed without having to go for a 30 km round trip to get coverage. This is the antenna https://app.box.com/shared/oqvat83ixekcjskpc3ug (not my design).

Yesterday, I went to the Aluminium Trade Centre on Dandenong Rd, Clayton to get some 10mm aluminium tube to make the elements for the antenna. (I have no interest in this business other than being a very happy customer who will definitely go back nest time I want aluminium. I walked away with enough tube to make four antennas for just $15).

On their display racks they have clearly labelled sample pieces, as per the photo below :aro-d:


303494

Straight away I think, "What a vast improvement over this: http://www.woodworkforums.com/f43/conversation-really-happened-no-enhancement-required-177419/index4.html This time around I didn't really care too much about the ID, but there it is. A commercial supplier who actually marks his display stock with ID's for his tube.

Initially I got a childish urge to post a line of ridiculous smilies in the post a bit like these:
:brava :)( :pointlaugh: :harhar: :woot: :hpydans: :roflmao2: :clap3: :yippy: :ohyaaa: :smack:

but I decided not to do that because I am far to mature to do something like that, but I am sure that a lot of you will understand how tempting it was.

Cheers

Doug

[wheelinround]

Doug you poor man to think that you have to stay tied to the world with an antenna not to mother nature and the wonder she has to offer.:q I know you just can't bare to be without your daily WWF updates can you.

[rustynail]

Camping is not camping if there is any form of outside communication.
C.A.M.P = Cant Access My Phone.

[Master Splinter]

The only thing the real world has going for it is a better framerate and high polygon counts. The gameplay sucks.

[BobL]

These are the important pieces of metal we take camping.
Top can be removed to make an open fore drum or BBQ.
The whole thing comes apart and fits inside our van.

http://www.woodworkforums.com/attachment.php?attachmentid=303513&stc=1

[doug3030]

Doug you poor man to think that you have to stay tied to the world with an antenna not to mother nature and the wonder she has to offer.:q I know you just can't bare to be without your daily WWF updates can you.


Camping is not camping if there is any form of outside communication.
C.A.M.P = Cant Access My Phone.

Guys seriously, making the antenna and trying to connect is a challenge I have taken on. Its not so much about actually connecting but the bragging rights you get if you achieve it. Several hundred people there last year and all everyone talked about was not being able to log on. On the mobile internet coverage maps, we aren't missing out by much, so if I make this antenna and mount it on the sand flag pole on the car and get it say 5 or 6 metres off the ground, 16.5db antenna, I am pretty confident I can get it to work.

Its a fairly cheap experiment:

Patch lead for mobile internet device: $16.50
coax connector: $3.95
Coaxial cable 15m: $18.00
Aluminium for elements: $15.00
boom (perspex sheet) $5.00

Finding TUBE sold by the inside diameter: PRICELESS

Cheers

Doug

[BobL]

Bragging rights if you can get it to work.

PRICELESS2

:2tsup:

[artme]

Doug It May not work at all!!

After all it's only Claytons aluminium!!:D:p:p

[rustynail]

"Several hundred people" is not camping. Its an inter city relocation.

[rrich]

Save you money on the aluminum.

Use copper screen mesh and build a "Bow Tie" antenna. Mount it on a piece of plywood and broom stick. You'll be able to solder your coax cable to the cobber screen mesh. The broom stick will allow you to raise the antenna above the ground squelch (Noise) and with a connector on the other end of the coax you can connect to your devices.

Cut the copper mesh into equilateral triangles and when gluing the mesh down to the plywood try to get the points within a few MM of each other. Solder your coax to the points.

Now the stupid question:
Isn't the purpose of gong camping to get away from e-mail and phones in general?

[doug3030]

Now the stupid question:
Isn't the purpose of gong camping to get away from e-mail and phones in general?

No, the point is to be the only one there who can connect, and then tell everyone that you can connect but you don't want to "because we are camping". :D

Cheers

Doug

[FenceFurniture]

There are many tempting aspects here, such as it ain't tube - it's pipe because it has an ID, so it may not work at all. Or maybe it's tipe or pube. However, I shall resist any further.

I wouldn't be at all concerned about the cost of it, in fact you could spend hundreds and recoup it all on the first day. Can you imagine the queues there'll be?

"HEY! Internet and mobile access over here for a $1 per minute!".:chase:

[FenceFurniture]

http://www.woodworkforums.com/attachment.php?attachmentid=303513&stc=1That's a cracker Bob! I have the classic washing machine basket on a stand which is nowhere near as classy. There's camping, and then there's camping with style and associated bragging rights.

We once found an old road fence post about 250mm in diameter that the termites had turned into a tu...pi...pube...tupe - upended it on top of the coals in the basket - instant metre long chimney. After about 10 minutes there was a sudden BANG and associated sparkles as the inside ignited to much loud inebriated cheering.

Oh and while your there, make mine a family sized "Daves" with an extra shot of pepp. Hold the Coke. 45 minutes?

[artme]

Certainly hope they are not pubes FF.

Could be a hairy thing to work on.:D:p

[FenceFurniture]

Anyway, surely the whole point of the exercise is this: Doug has to make the antenna so that he can instantly post piccies of the queue of people waiting to get on-line. Or better still, Webcam the event.

How else could he do that?

[rustynail]

The only decent queue is a BBQ.

[mike48]

Concerning the antenna aspects of this thread only ...

If I were making something like this, I would ...

Use 20x20 mm RHS aluminium as the boom, redesigning the element lengths for conductive boom.
(Removes the need to drill the boom accurately for the elements).
Use 20x6 mm flat aluminium for the elements, other than the driven.
But you have already bought the tubing, so...
Screw (304/316 SS) or rivet (AL+AL) the elements to the boom.
No need to worry about the "electrical" connection of elements (other than the driven) to the boom; it has no effect whether they touch electrically or not, for this design.
Use a balun (a number of smallish loops of coax cable in a coil) as per original design, but must be in low loss coaxial cable.
Use low loss 75 ohm TV type foam cored coax cable for balun and feeder. (Do not use RG58 or ordinary RG59).
No need for 16 million shields on the cable, one will do, but most cables of this type are now quad.
Use coax adaptors to mate with modem or phone.

The lengths of the front directors seem a smidgen short, and 1/2 wave at approx 1200 Mhz?
May be correct, as the driven is about right.
You will probably achieve the required bandwidth anyway at this frequency, due to "construction constraints" (unintentional dimensional and construction compromises) and the diameters of the directors and boom.

Just suggestions.

Good luck, and let us know how you get on please.

cheerio, mike

[q9]

If I were making something like this I'd go on ebay and buy a yagi antenna kit for about $30...

[doug3030]

Concerning the antenna aspects of this thread only ...

If I were making something like this, I would ...

...

Just suggestions.

Good luck, and let us know how you get on please.

cheerio, mike

Hi Mike,

Thanks for your interest in my project.

I actually want to make a few different antennas from here: http://whirlpool.net.au/wiki/homemade_yagi#homemade_yagi_pg2 (where the earlier link to the antenna came from)

While there is a certain attraction to a 16.5db antenna, there is another attraction in an 11db antenna that is only 1/5th as long; much easier to put up the mast and then you can pick the smallest antenna that will do the job.

I am experimenting with a construction method that will allow strength and rigidity without too much weight and can flatpack in the back of the ute in spaces that can't generally be used as useful cargo space.

Between now and Easter I will be working on these ideas with 850mhz NextG as well as 1800mhz LTE antennas.

The antennas themselves are cheap as chips. For my $15 worth of aluminium I can make every antenna I could possibly want. Allowing for the cost of the boom and some coax connectors I can make one of the smaller antennas for about $7 and the biggest ones I want to make for about $15.00. That's why I wouldn't even consider a $30.00 yagi kit on ebay. Most of the cost of the project is actually the patch leads to the phone and the wireless internet device and the coaxial cable, which I doubt would be in the ebay kits. All the antennas can share the same coax and patch lead in the experimental stage.

Yes, I will post some results, but I am not one to document every hole drilled or cut made.

I will probably post some photos of finished antennas and a bit of a write-up of construction/design details and how they perform.

Just dont expect it tomorrow, or the next day :rolleyes:

Cheers

Doug

[q9]

Some come with leads some don't.

Here (http://www.ebay.com.au/sch/m.html?_odkw=&_osacat=0&_armrs=1&_ssn=rfbat&_trksid=p2046732.m570.l1313.TR11.TRC1.A0.Xyagi&_nkw=yagi&_sacat=0&_from=R40)for those that don't have the ability to make their own.

[mike48]

G'day Doug

I really doubt that you will find any high gain 900MHz band yagis on eBay for less than $100 or so.

Yes, connectors etc form a large part of the constructor's cost.

That Whirlpool website is always worth a look on many of these subjects.

mike

[doug3030]

Some come with leads some don't.

Here (http://www.ebay.com.au/sch/m.html?_odkw=&_osacat=0&_armrs=1&_ssn=rfbat&_trksid=p2046732.m570.l1313.TR11.TRC1.A0.Xyagi&_nkw=yagi&_sacat=0&_from=R40)for those that don't have the ability to make their own.

Hi q9,

thanks for the link.

Those antennas on the link look quite good and reasonable for the price, but they are not suitable for my purposes.

The frequencies they are tuned to are not the ones I am targeting. For my camping trip at Easter there is no point in looking at any other frequency but 850mhz Next-G. The higher frequencies just wont have the range to get to where I am going no matter how big the antenna.

The 16db gain antennas in your link are for 2.4 ghz, a much higher frequency and therefore can be a lot smaller for the same gain. The ones in the link are less than half a metre long whereas the one for 850 mhz is just under 2 metres long. Even the Chinese wont make you one like that for $30.

The higher the frequency the higher the data rate but the shorter the range. The lower the frequency the slower the data rate but the longer the range (as a general rule, all else being equal)

I did mention making some 1800 mhz LTE ones too but they wont be any good where we are going. There is no 1800 mhz tower anywhere near where we are going this time but they may be useful in other destinations, for example camping close to a larger rural centre that has 4G coverage.

Cheers

Doug

[FenceFurniture]

So, Doug, how much did you make over the weekend? :D

We did expect a report you know - like from the site itself - realtime and all that.....

Just a guess, given the absence of any report: it didn't work.

[doug3030]

Just a guess, given the absence of any report: it didn't work.

Thanks for the reminder Brett.

The antennas do work but I was not able to get a signal where we were camping.

I did trial them in areas of low signal before we went and they did very successfully boost the signal.

Once we left the camping area yesterday I drove past the site of the phone towers and they are very close to the ground, seemingly only there with the intention to serve the township and not much of the surrounding area.

The antennas will still be good for other places and there may be a couple of things I can try differently next time I go back to where we were for Easter.

It was still a worthwhile experiment. If nothing else it was an exercise in getting precision results on a drill press.

Cheers

Doug

[FenceFurniture]

If nothing else it was an exercise in getting precision results on a drill press.It's worth waaaay more than that - finding Tube with an ID is, as you said before, "PRICELESS".:D