BUD Kit and transatlantic reception

[guapoharry]

Thanks to vfrjim there was a lead in the FTA Shack on an interesting 12 foot BUD kit being manufactured. Check out page 92:

TELE-satellite International Magazine

Index: http://tele-satellite.com/content/eng/0901.pdf

Download: http://magazine.tele-satellite.com/TELE-satellite-0901-eng.pdf

The article says that dish is too crude for good Ku reception, but works fine for C band. That multi-LNB photo on page 96 is pretty interesting too.

This got me to thinking about how one could fab the frame. Making a spheroid frame would be pretty easy using Harbor Freight Tools rolling mills and what not. So then, how could you create/modify a bender to make parabolic radials?

Also, on page 98, some guy in the Canary Islands reports getting 61.5, Amazonas and Hispasat. Then the writer invites people on the american east coast to report on getting european sat. reception. Given a sufficiently eastward big dish, why not? Suppose you were in Puerto Rico? Maybe it would be worth a try.

 

[Lone Cloud]

Parabolas

There is a way to create a parabolic shape, which, if it were traced onto a piece of poster board, you could compare the ribs you are bending to it.

Remember, owiing to the distance of the transmitting satellites, the signal comes in essentially straight at the dish, and all signals are then reflected off of the dish surface to a focal point at the lnbf,a, etc.

It is basically done with a big square, a string, and a pencil. One end of the string is fixed at the focal point of the "dish" and the other end is attached to the square at the square's top end. A pencil is kept against the square edge and and in the "v" of the string and, as you move the square toward the focal point, you follow the square's edge downward, keeping the string taut.

You end up with a parabolic shape.

Unless you'd enjoy such a major project, wouldn't it be easier to hunt for an unwanted BUD already made?

 

[Anole]

Back in 2004, the Aussies decided to play around making their own dishes.
They have a thread covering how to get the parabola, how to make ribs, what to cover the dish with . . .

Not too practical project, but I recommend it for a good read! -

Unless you'd enjoy such a major project, wouldn't it be easier to hunt for an unwanted BUD already made?

Damned right ! - :up -
I came to the same conclusion... but not until after discussing it with a number of buddies.
We considered metal-working tools, metal jigs, wood routers, and many ideas on sealing the dish against weather.

 

[guapoharry]

Back in 2004, the Aussies decided to play around making their own dishes.
They have a thread covering how to get the parabola, how to make ribs, what to cover the dish with . . .

Not too practical project, but I recommend it for a good read! -

Unless you'd enjoy such a major project, wouldn't it be easier to hunt for an unwanted BUD already made?

Damned right ! - :up -
I came to the same conclusion... but not until after discussing it with a number of buddies.
We considered metal-working tools, metal jigs, wood routers, and many ideas on sealing the dish against weather.

I totally agree with all-y'all about the trouble factor. But think about it... Suppose if you devise a clever means to bend the parabolic radials out of steel tubing. You could crank out BUDs in quantity and fill your yard with dishes.


That aussie project was interesting, but wood material would not be suitable.

 

[Lone Cloud]

I thought about that too when I didn't have a big dish. I figured I'd cut the parabolic dish shape out of plywood, and attach a rod to the middle of the plywood, stick the rod in the ground and then dump some concrete under it.

I figured I'd spin the plywood on the rod and keep adding concrete until the plywood template touched the concrete all around.

Then I figured I'd use the hardened concrete as a mold and fiberglass up a dish. I figured I'd either embed a metal screen in there or tape on aluminum tape after it hardened.

Then I found two big dish owners who begged me to take away their dishes.

Fill your yard with dishes? You don't need to fabricate them yourself to do that. They are there practically for the taking

 

[Anole]

covering material

I once did a consulting job for a guy making things with a "stretch press"
Think that's what he called it.
Basically, he took a big piece of metal (an I-beam sometimes), grabbed it by both ends, pulled like hell with a hydraulic jack 'till it was under tension, then wrapped it around a form (mandrel).
When you released the tension, the piece held its shape.

You'd only need one form to make one rib...
How 'bout one inch aluminum tubing about 6' or 8' long?
Crank out a dozen or so, tie them together in the center with a plate.
Then, maybe have a smaller diameter rim to go around the outside ?

How to fill in the reflector?...
This question has also come up a few times and I've never heard an answer:
...can you cover the dish with aluminum screen wire mesh?
Ya might use self-taping screws with washers?
No, what about pop-rivets?
I'm sure you'd find something better.
But as you say, you could crank out a big dish quickly and accurately.
It wouldn't be too expensive, and could probably be pretty light.

Bending the rib to a parabolic form would be the task.
And the Aussies had plenty of good ideas, so that thread is still a good basis for anyone thinking of following through on this idea.

 

[rv1pop]

Boeing builds a parabolic dish or two into every airplane, but they call them pressure domes! As you surely know, building the tin dishes is not the expensive part, shipping is. Looking at airplane wings and the precision they have, forming petals is old hat now days: form a petal out of aluminum, forming the inner and outer ribs, prepunching the line up holes can not be that hard. Then stamping the polar mount and making angle iron attachments - adjustable for elevation and declination .... With enough petals - each 3 feet long and however wide you would need would ship UPS or FedEx. Might take several packages because of the weight but.... With the present cash flow crunch I imagine an aircarft parts supplier might want to take a look at it. A 3 foot, 6 foot, 9 foot, 12 foot, 15 foot all pre-fabbed. Possibly on the same tool, or at least with the same press, maybe different dies. Dreaming? Cost to build would be offset by shipping savings.

 

[Anole]

Pop - I agree with you completely.
Not a new concept (agreeing, that is) , we often see eye-to-eye. -

There's only one shortcoming:
D E M A N D -

Solve that, and we'll be drowning in fancy aluminum-petal dishes!

If they were for the do-it-yourselfer, maybe he could roll on his own paint.
And pop-rivet the panels, possibly to some ribs.
Sign me up ! - :up

 

[rv1pop]

Yes, Anole, That is the idea. DIY dishes. Watching the jig and tool makers building wooden tools to stretch panels from aluminum gave me the idea. With the small curve needed the pressure would not be too great IF the panels are small enough WHICH makes them shippable. The lips would need to bend first so they can stretch out with out wrinkling the main panel. I would almost bet Chrysler could be shipping panels to the SatGuys before Christmas if they wanted to. Ford might if they were shiny BLACK! Who needs cars if you can watch Satellite TV?

Maybe that would rejuvinate the car industry!

A C-BAND SATELLITE DISH WITH EVERY NEW CAR SOLD IN THE NEXT THREE MONTHS!

{shouting intentional}