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Alternative Uses For an Old Satellite Dish?
ya really writes "My family has one of those BUDs (Big Ugly Dishes) sitting in their back yard still. The other day they asked me if I would take it apart for them. Aside from simply recycling it, I was wondering if there are any alternatives for its use. It was one of the last made before DirectTV and Dish took over satellite broadcasting, and even has a digital receiver. I'd say it was made around 1996."
Bird Baths...
Satellite dishes make excellent directional 802.11 antennas.
Just remove the existing LNB from the dish and replace it with a homemade antenna, like a biquad, tuned for your band-of-interest (i.e. 2.4GHz ISM for wi-fi). Make sure you get a powerful (high RX sensitivity & high TX power) wireless card with an external antenna jack
Here is one project write-up, though I'm sure there are many others:
http://www.engadget.com/2005/11/15/how-to-build-a-wifi-biquad-dish-antenna/
Alternatively, keep the LNB, get a DVB capture card (PCI models go for $20-$80+ new), and use the dish to get FTA (free to air) satellite TV.
There are many communities for this kind of thing exactly, just search google for: FTA forum
I'd also take apart that digital receiver and reverse engineer the hardware as much as I could, just for kicks.
When you've gotten your hour of fun out of it, gut it for parts and move on to the next interesting project.
Full size satellite dishes are still the best way to receive free television content, despite what the cable / pay satellite providers may imply in their advertising. If you don't have any place to put it yourself, it shouldn't be too difficult to find someone who would be willing to buy it.
-- The act of censorship is always worse than whatever is being censored. Always.
Get a C band LNB and point to the next C band sat that is out there.
Plenty of C band channels out there. A good list is here.
http://www.lyngsat.com/america.html
Rob from Cockeyed.com made his own Archimedes Death Ray and it worked:
http://www.cockeyed.com/incredible/solardish/dish01.shtml
You could also:
-73, de n1ywb
www.n1ywb.com
C-Band is still in fairly active use in the US and around the world -- you could (gasp!) use it for what it was built for. It's the only way to get truly ala carte TV service, and usually costs a lot less than the alternatives (not to mention all of the free stuff out there). You'd probably need a new receiver to get digital channels, but I've spoken with plenty of MythTV users who have C-band setups.
Do you really need reason for beer? Wingman Brewers
Some lads with a couple of your dishes cracked 125 miles during the 2005 Defcon Wi-fi distance shoot out. With your one dish on one end, and even the weakest built-in wifi antenna on the other, you can still create a solid network connection to the next County. If the other antenna is a run of the mill 15 or 24 dB directional wifi, you can really crank.
Luke, help me take this mask off
But Why??
That would destroy the "habitat" of the Spelling and Grammar Nazi's on ./
Where would they go? What would they do? They might actually be forced to read articles and post actual content instead of editing the rest.
Come on, have a heart. If an occassional spelling mistake makes it into ./ which gives their lives meaning, let them have it.
From your link to wikipedia:
Although a single cable is limited to 5 meters, the USB specification permits up to five USB hubs in a long chain of cables and hubs. Consequently the maximum possible signalling distance is 30 meters, using six 5-meter cables and five hubs. In actual use, the last hub is a more convenient endpoint since some USB devices include built-in cables intended to directly connect to a hub, setting the maximum useful signalling distance at 25 meters.
Also note that the maximum length of 5m is due to the standard allowing for a cable delay of less than 5.2 ns. This means that a 5m cable will be under the 26 ns allowed delay. If a cable introduces less delay then it would be possible to use a longer cable.
I wrote about think kind of thing briefly in my journal a while back: http://slashdot.org/~evilviper/journal/189083
You've already got most everything you need... For the cost of a DVB-S receiver ($40 for a PCI model, $100 for a set-top-box), you can get quite a few free TV channels, in addition to raw feeds and other eccentric stuff. No monthly fees required. That doesn't include most "cable" channels, but much more than you'll get with an antenna.
Alternatively, if your dish was already fitted with a Ku-band LNBF, you could simply aim it at the DirecTV sat, and get a VERY strong signal, eliminating drop-outs even in the even of airplane flyovers, or extremely heavy rain fade.
But I would suggest throwing out the DirecTV subscription, and going with the big-ugly-dish you already own, and a 4DTV receiver. It's easily the cheapest way to get subscription channels, probably less than 1/4rd the price of DirecTV or DishNet. Ala carte subscriptions are a big advantage that could save you dramatically.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
You can get the DVB card, and install magic software for it then you can get free Pay TV.
there are few magic plugins for mythtv and you can get dishnetwork free all digital
That's too obvious. If you're going to make a "weapon" out of it, at least make a HERF gun. Don't even have to silver it for that ;)
If you are going to silver it... hmm, how perfect of a parabola is it? If it's good enough, or if you could machine it to that good of precision, you could use it as the primary mirror on a huge truss tube telescope.
No, she's fine. My associate is vomiting for a totally unrelated reason.
Either grow a massive hedge in an orb shape and stick this dish in the top section just like the DeathStar from StarWars...
To further illustrate the concept, check out this T-shirt.
If life is a waste of time and time is a waste of life, let's all get wasted and have the time of our lives.
Shouldn't be that hard to hit a groundhog with a 12 gauge, depending on what you're loading it with. Really, all you have to do is point it in the right direction. Impressive, nonetheless...
If I don't put anything here, will anyone recognize me anymore?
No, you can't use a BUD C-band for Ku-band reception because they resonate at different frequencies. They make large Ku-band dishes, but you probably don't have one. A 36-inch Ku-band dish will get anything you need to get anyway...but I realize you're trying to find a use for that huge hunk of steel.
you can't use a BUD C-band for Ku-band reception
True for a C band LNB, but assuming you have a dual (C and Ku) band LNB the problem then is not resonance, it's selectivity. Most C band dishes have a fine enough mesh to reflect Ku band signals, but at Ku frequencies BUDs are not always directional enough to keep signals from adjacent satellites from interfering. You'll still get most of the Ku channels, but every once in a while you'll find one that you know you should be able to receive but can't. I had this problem with ktwo. I knew it was there, Lyngsat told me so, but I just couldn't pick it up until I installed a dedicated Ku band dish.
A 36-inch Ku-band dish will get anything you need
I agree - if you're in the continental US and don't have anything getting in the way like tree branches, a 36 inch dish is all you need for Ku.
You can absolutely use a c-band reflector with a ku feed. The focus is the same regardless of the lamba (wavelength in meters [or lambda] is 300/freq in megahertz.) You'll see that the reflector (dish) is multiple lamba and non-resonant for either c (4ghz down 6 up) or ku (11ghz down, 14 up) so moving to a higher band effectively increases the size of the reflector, but the reflector is not a resonant peice, and a grid dip meter will show that. ... hydrogen absorption limits the trend in actually using anything past ka...
He was likely bluffing. DirectTV uses NDS Videoguard, which AFAIK to this day remains unbroken. There are other networks out there that can be broken, and many of them require buying a "Common-Interface" card (basically a PCI-PCMCIA adapter) and a decrytion module.
There is nothing "resonant" about a parabolic dish, the diameter determines potential gain and the shape is a function of the focal point. Gain increases as the wavelength becomes shorter in relation to the dish, so most dishes are more effective at Ku than C, which is why smaller Ku dishes provide similar gain figures to the old C band dishes. A common problem is that the mesh of the older BUDs is not tight enough to be reflective at shorter wavelengths, but most were dual-band C/Ku toward the end. Another design constraint is the "illumination" angle of the feed horn, in other words, the amount of the dish the feed can "see". Dish surface outside the illumination angle of the feed is useless, which is why we don't see very shallow dishes with the feedpoint very close.. these would require a feed with a wide illumination angle. The reason you don't go with the largest dish possible, besides space limitations, is that increased gain narrows the beam width of the antenna, which means it must be pointed with more accuracy. A small dish might provide sufficient gain when pointed within 10 degrees of the source, a huge dish might be a fraction of a degree. An 8ft dish used for Ku would be hard to point, but would provide phenomenal gain, probably more than most Ku band LNBs are being designed for these days, and I'd imagine it would overload if you couldn't turn down the gain of the amplifier. If you are providing more signal than your amplifier can handle, you've got either too much antenna or too much amplifier.
I spend less than $100 USD per year and get 4,000 channels off my BUD. Some are digital stations others are analog -- just like cable and other satellite technologies. There also HD options for BUD but I don't have the hardware for that. I am happy with the local HD programing I get from rabbit ears.
Use it for observing the radiation emitted by passing communication satellites, particularly in th 4-8Ghz range.
Just be careful with that microwave oven. Those magnetrons can be dangerous.
Thanks for posting the warning. My post was humor. I used to repair the ovens in the electronics shop, so I am aware, however the causal reader of Slashdot should heed the warning. They typically operate at about 4KV. If the HV doesn't get you right away, the effects from exposure to the radiation or dust from a smashed magnetron could produce lasting lingering health problems.
The truth shall set you free!