Converting a 90 cm dish to a 1.2m dish

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Here's the dish with the petals connected with fibreglass blanket and Bondo. Messy looking right now, more work is needed but looking more like a dish than a giant sunflower. Put a Ku LNB on and will adjust it for tracking the Clarke Belt. Using an old Sadoun H-H motor. Dish is still light enough despite the additions.

Beats mowing the grass...
 

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Interested in learning before and after signal readings.
 
Here's what it looks like so far. Kind of looks like a big sunflower. Next will get some wire mesh (screen) and connect the petals. Might be a total waste of time but never know until you try. If it does not work out then at least I can say I tried it.

All your missing is some paint!
 

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That's a pretty dish you have there Kraven!
 
Need a good logo to put on it when done. Maybe a big sponge for sopping up the sat signals hi hi.

Like Kraven's dish too.
 
They don't make a perforated one for my 305cm dish. :(
 
I expect that you will observe increased side lobes and I am going out on the limb here to suggest that even on a satellite without adjacent satellite interference, the BER will be higher due to the surface inaccuracy on the new reflector real estate. Hope that you have some pre-mod readings to compare. Yes, different conditions, but it will be interesting to compare with several satellites and transponders.

An example of adjacent satellite interference is 97W, 11842. This transponder has significant interference from 95w and the BER is reduced and the Signal Quality climbs as a dish is panned to the West away from the interference and also off of 97w. Other transponders have better Signal Quality readings when pointed directly at 97w, because these TPs do not have the same adjacent satellite interference. Will your "Frankendish" exhibit the same increase in Signal Quality when panned slightly West off of 97w?

It would be interesting to observe the spectrum display as the dish is panned. Not scientific, but you should be able to see the signal increase as the satellite is received on a side lobe and not the main center lobe.
 
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What about cutting up an old six foot prime focus dish and using that as raw material? A pair of tin snips and a welding outfit and ready to go.

But would that be converting a 90 cm dish to a 1.2m or converting a 1.8m to a 1.2m? Confusion is setting in....what is really happening....where am I?...must be the Bondo fumes....beam me up Scotty! :)

Those dish covers are great.
 
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I'm going to start a new thread on this probably this weekend and post some pictures, but I figured with the topic and discussion within this thread I'd put up a post here cause some of this probably could be applied to extending the size of a dish.

I stayed home from work yesterday because the brakes on my car messed up and after I fixed the brakes, I decided to try out a idea of making a dish that I've been tossing around in my head.

I have a mount for a 76 cm dish here with no dish part, the dish part was bent almost in half when I got it, so I'd scrapped that and kept the mount and arm assembly. If it weren't for having the mount/arm assembly with no platter, I probably wouldn't have tried this! The mount looks identical to the one on my 76 cm Winegard except the LNB arm is oval instead of square, the part that actually bolts to the platter is identical, mounting holes,etc.

I took the platter from my 76 cm Winegard, laid it face up on a barrel and covered it with aluminum foil, sealed the edges of the foil with aluminum duct tape and then covered that with fiberglass cloth, stuck the four mounting bolts through it and put the nuts on the back side, then covered the whole deal with fiberglass resin. Once the fiberglass had hardened, I popped it off of the metal Winegard dish. The whole thing right now is butt ugly because I didn't sand it at all or bother sealing up the back side because I wanted to see if it'd work before I wasted anymore time/money on it.

Set my Winegard 76 cm on 95W and for CCTV I got a Q of 74% on the MicroHD. Swapped out the metal platter for the foil/fiberglass one that I'd made and I was surprised, got a Q of 75% and didn't have to adjust it at all.

Looking at the thing, I had doubts that it would work at all, like I said, it's real ugly looking right now, but I'm going to clean it up some, seeing as it did work!

It was kinda pricey and took about an hour working on it, it cost me $29 for the resin and $7 for the fiberglass cloth and I'm still not done, I still have to fiberglass the back and clean up the edges, so to actually do this instead of buying a dish wouldn't really be worth it, seeing as how you can buy a 76 cm for $40 something and $20 or so shipping. Was fun to do though and if something like cardboard or whatever could be fitted around a dish as a mold, maybe a dish could be extended in size this way.
 
Very interesting idea A Raine, so using the old dish as a template you basically made a copy, that is great! Definitely thinking out of the box. For experimenters this is a useful idea. That's sort of the thinking behind extending the diameter of an existing dish.

The four foot expanded dish was tested initially on 99W C and got Channels 1,2,3,4,7 (7 has a hot TP but no broadcast) Shepherds Chapel, Lesea, and GDMX channels. One channel is from U.S.V.I, other is PR. Did not sand it smooth yet, as I want to test it on 18W - 131W C and also the Ku band.

Recently spoke to someone who has been into TVRO from way back when, he said there used to be a company selling circumferential retrofits to increase the diameter of an existing BUD, so someone had the idea previously.

Thanks for sharing the interesting project.
 
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With a 3D printer I can envision someone making their own dish, heck there's a guy in MAKE magazine that made his own violin from a 3D printer. Clothes have been made too.
3D printers can make the average Joe/Jane a manufacturer of parts, devices, etc, right out of a small room in the house. A mini-factory if you will.
 
What they need now is a scratch and sniff sticker the whole neighborhood coming over to scratch your dish and smell it. You come out smelling like a rose in this situation.
 
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