Slashdot Mirror
Using an Old Satellite Dish as a WLAN Antenna
=m8s=Dark Underlord writes "I was browsing for wireless stuff and came across this link that shows how to use an old satellite dish as an 802.11 antenna." The directions tout the range as being 10 miles given line of sight. We've had other stories about building antennas, but I think these are cooler because of their focused nature, but a Primestar dish is a little tougher to locate than a Pringles can or a floppy disk.
The Original Slashdot Article
Looks like you can pick up a Primestar dish on eBay for about 50 bucks (current auctions here). Shipping looks to be about $20. Anybody know of other sources for acquiring these dishes?
.sig
Aren't you supposed to return the antenna at the end of the contract?
Days ago. And IIRC, it was a /. article that inspired me.
You can't judge a book by the way it wears its hair.
Making a WiFi antenna using a telephone poll. You use the red and green wires to transmit a signal to another WiFi device connected to the red and green wires up to 20 miles away. But what would I know? I'm just a naked chick.
--
So I'm naked. So what?
Primestar dish is a little tougher to locate than a Pringles can or a floppy disk.
Will a DISH Network or DirecTV dish work? I can locate hundreds of these without walking too far. Give me a couple of nights and I can send a bulk shipment you're way for a few thousand dollars.
Now, where did I put my screwdriver?
-- Fighting mediocrity one bad post at a time.
ahh the good old days of Living Color with Jim Carrey impersonating Vanilla Ice
MoFscker
I saw the tin can at the focus point of the dish. Wouldn't a Low Noise Block (LNB) converter be more efficient for signal transmission?
A few years ago I saw one still attached to a pole near an old trailer foundation along the highway. A few minutes of working it loose and we threw it in the trunk. I had plans to buy a receiver on ebay and get C and Ku band channels but never followed through.
Only the State obtains its revenue by coercion. - Murray Rothbard
I tried this a while back, but at the time, even unused sattelite dishes were too expensive. I borrowed a neighbors' dish for the experiment. The hard part was focusing the dish - If you didn't have something sturfy to mount it to, then you would lose the signal pretty easily.
My grandparents have a satelite dish that's about 10 feet in diameter... so should that give access to about 30 miles away? (I know it wouldn't, but it'd be neat to crank the amps)
Karma: Good, or bust!
Where I work our internet connection is via a WISP that uses this "technology". We have a Primestar dish on an elevated pole aimed at a mountaintop 12 miles away. 5Ghz and also a backup 802.11b radio with Yagi antenna that needs an amplifier to go that distance, but does so fairly well. The less-informed employees think the "dish" points to a satellite, not noticing the odd angle it's mounted at :)
http://www.planetc.com/ is the ISP
but it is powerless against slashdotting!
Satellite dishes aren't hard to find; just visit any trailer park or upper-lower/lower-middle class neighborhood, and I guarantee you, there'll be a dish stuck on the corner of every other house. The kids'll be running around half-naked, there'll be a car or two on the lawn, but getting satellite tv still seems to be first priority.
It was just difficult to convince my wife to keep it. Lucky I was successful....
Why bother with the Primestar dish for $50 on Ebay when you can get a real 802.11b/g antenna with 24dB gain for about $65? If memory serves, every 3dB is double, so 24dB is 2^8 or 256 times the signal strength.
I STILL say my dish is better than anything you can get. Damn, I can WiFi to my brother's computer all the way in Zeta-Twelve!
wwc.edu better set up a bunch of these things and stream the site to someone with more bandwith...
SAILING MISHAP
Google Cached Version
what an LNB actally does and why this is an absurd notion?
http://216.239.53.104/search?q=cache:ltX22XDG3_4J: www.wwc.edu/~frohro/Airport/Primestar/Primestar.ht ml+&hl=en&ie=UTF-8
I've got the page and images...if anyone want's to host a mirror post to my Journal please.
.sig
google cache
Hey, guys, this would violate FCC part 15 and other applicable rules. Specifically, we are referring to ERP (effective radiated power).
Have fun if you get nailed!
If your symbols crash, try increasing the size of your hash table.
Waitaminnit, isn't this 1978 and am I not writing in Z80 assembler?
If you are interested in this, check out the Canteena solution which has a 12 db gain. You can get a *new* shiny antenna for much less than the cost of a used Primestar dish on EBAY. I know the dish in the article boasts 22 db gain with a 10 mile range but, keep in mind that setting up communication that is line of site 10 miles apart is nearly impossible. (Just try using a camera with an 8x telephoto lens to take a non blurry picture, you'll start to get the idea. ) Have fun!
uh, no ... asshat
Theres even a 50 foot homemade dish for ham radio. Build your own big dish
My dish network is not fixed, and has been working for over a year. I use an old carpet to prevent sliding, and place it against a wall on the side and a box on the back. It has been surving 35mph winds.
The hard part is pointing it, but once getting it right it is easy to replace it in position.
Given the fact this story was just posted on Slashdot..not for long.
Somewhere, tomorrow morning, some poor satellite dish dealer in East Nowhere is going to be very, very happy and not know why.
Please help metamoderate.
You can get one of the big dishes and an echostar box from a pawn shop and try to pick up analog C and KU band channels. Some semi-premium channels are still unscrambled. AFAIK you can still subscribe to big dish services. Apparently a cleaner signal and no mpeg artifacts.
"- Sir, you are aware that you have a huge TV antenna duct-taped to the roof of your mini-van?
- Hun, yeah, I do
- And that there seems to be 2 sets of eyes in the back of the mini-van that look like they belong on ghouls
- I think you mean geek sir. And don't mind the flashing leds too, we are having a lan party.
- In a mini-van ?
- Mmh, yeah.
- Ok, drive safe"
*rolls up window and keeps on following the signal*
In Canada, we don't fancy things like socks
Use this and get truly large distances.
"A great democracy must be progressive or it will soon cease to be a great democracy." --Theodore Roosevelt
In a past life, I used to provide ISP services to a company in Iowa that manufactures dishes used by many of the top names, including DirecTV. I checked their website, www.winegard.com, and it doesn't appear they yet have a consumer distribution channel. But if you want a bunch of dishes, these folks can probably provide them.
FWIW- I toured the plant, and saw sheet metal stamped into dishes. It was impressive.
I recently moved into a new duplex. One of the things that really annoyed me was a "largish" primestar dish cemented in the ground in my back yard. Looks like I may be able to get some use out of it....
Imagine the long distance LAN parties.. whoa yah.
Call your buddies up around the neighborhood and your ready.
ogg
Black cat, searing pain, flames...? I must be in Heaven! - Homer Simpson
Did you ever think to RTFA...
"A Primestar dish. (You may use any old dish, but if it is bigger than the Primestar the gain will be higher, and it may not be within the Federal Communications Commission rules for use within the United States. In fact I have come to find out that there seem to be several different dishes that Primestar used, and I am only sure that the one I used, pictured above, used with the ordinary Wavelan or Airport transceiver card is within the effective radiated power limits given by the FCC.)"
Do I need to worry about being charged for man slaughter if i set this up and grandpa's pace maker stops?
All your base are belong to us!
Of course this could easily violate the power limitations on the device rendering your setup illegal. But with the things the FCC lets slide these days...
I extend condolances to everyone who does not have an extra dish or the intillegence to find one.
Please post your personal success or failure to make this thread worth a click.
M@
Krispy Cream is people
Ok I understand the curvature of the Earth thing. But damnit! HAM Radios don't have to be line of site. Why the hell do I have to be within line of site of my friends house to reach his bandwidth!
-illumina+us "I put on my robe and wizard hat..."
"I sacrificed a db of gain here by not turning it over, mostly because I'm mounting it on a vent pipe, and didn't want to put that kind of wind load on it. As mentioned above I don't really need the extra signal either."
Wonder if he realizes what that vent pipe is for? Are there any studies on the interference factor from 'methane gas' emmisions on WI-FI?
Maybe it's just the bathtub/sink vent.
sig mind freed
So tell us stranger...
What is it like living in the future?
You can't judge a book by the way it wears its hair.
Unless you are actually worried about taking up too much space (and why should we let that get in the way?), why use one of those little mini-dishes? Go all out and find an old 8-ft diameter big dish system. Not only will get a much larger reflector area, but if the control arm and box are still in working order, you can remotely slew over an arc of about 50-60 degrees without modification. This could let you change focus to different nodes from your computer.
Plus it is far more conspicuous, and therefore infinitely more cool.
There were two dishes still attached to a couple of burnt out houses near where my sister lives. When I visited her I wondered if her home owner's association would let me have them. Next time I came by, the houses were half torn down with the dishes no where in sight. I wish I'd known when they discarded them. I now regret not haven taken them when I was there.
Stay sentient. Don't drink bad milk.
There are much better solutions. While a pringles can and cantenna might work, assumng you put it right in the focal point, build the cantenna right, and can find the dish, this might be a better way to go:
Try this.
Its a 24dB gain antenna (Thats 256 times power folks), its guaranteed to work, it HAS a feedhorn, and all the calculations have been done for you. Not only that, its a grid antenna so there is almost no wind loading. You might pay 50bux or more for a primestar dish on ebay, plus trying to get the can into the focal point, etc. There is certainly a certain apeal in doing it yourself, but sometimes work for the sake of work is no fun at all.
The best thing? Its only 70 bux, WITH the feedhorn and pigtail.
Right now im using one of those, and two 10 foot C-band dishes to make a big triangle network connection. The C-band to C-band dish connection is over 30km long. (Yea I'm in Canada: 30 kilometers = 18.6411358 miles)
It's easier to fight for one's principles than to live up to them.
I have an old one in my back porch, DISH sent me a new upgrade and I have no use for the old. Well until now.
I am sure it's a hoax. I still remember the old /. story mentioning floppies. I spend a week trying to convert a bunch of 5 1/4" floppies but didn't get any gain - none AT ALL! :( Maybe I should have used 8" instead?
Sure, it looks big and impressive, but that's just not top-of-the-line anymore. If you're going to do serious networking, you'll need a bigger antenna!
It is perfectly legal. in fact, the FCC encourages directional antennas. Go and read the regulation.
Oh well, what the hell...
For what it's worth, two Linksys WAP11's in bridge mode, and two directional 24dBi gain antennae, and my link is rock solid at 1.1 miles.
I use Linksys WET11 bridges with 24dBi grid antennas made for 2.4GHz (also less than $70 each) and have a rock-solid 11Mbps link a bit over 6 miles away. The trick is to mount your WET11 in a weatherproof box right underneath the antenna, to keep the coax pigtail as short as possible, because signal loss in a long coax is the distance killer. I have only a 3 foot long coax pigtail and run the dc power up the unused pairs of the CAT5 cable to power the WET11. You may have a significant voltage drop at the end of a long CAT5 cable, so you may need to use a +6V or even a +7V DC power supply of adequate amperage to ensure that you still have +5V DC at the end of the CAT5 cable with the WET11 plugged in loading it down. I had to use a +6V, 1.5 amp DC power supply on mine to keep the voltage at +5 volts at the end of my CAT5 cables, or the WET11 wouldn't run.
You won't click it if you know what's good for ya. BWT NOT WORK SAFE!!
My bad that should have been http://www.ntfs.com/
Charles Miller
The more I learn about the Internet, the more amazed I am that it works at all.
You could use that to link up with Carl Sagan. Surely they've evolved wireless tech that's backward-compatible to 802.11b in his galaxy by now.
Withdrawal before climax is very ineffective and those who try this are usually called "parents."
Only the party obtaining the FCC certification is allowed to specify another antenna. You, the user, cannot alter the device even if it meets the requirements of 15.247. Modifying approved transmitters is generally not allowed, with the notable exception of the Amateur Radio Service. A new configuration with higher antenna gain requires a new certification. 47CFR2:
[emphasis added]So unless you have the money to spend on a complete recertification (it's neither cheap nor easy), leave your wifi alone!
Read ALL the regulations, starting with Part 2. The technical limits in Part 15 apply to the "responisble party" who obtains the FCC certification. It has nothing to do with user antenna modifications, which are expressly forbidden by the regulations. Any user modification is forbidden, except for Part 97 use (amateur radio)-- and amateur radio cannot be legally used for public wifi setups.
How the heck do you sight something like this in? You have to be accurate within a few seconds, don't you? A search pattern would take forever with that narrow of a beam, wouldn't it?
The beam isn't that narrow. Let's do a quick mental calculation. A typical direct-to-home Ku-band dish is going to have a beamwidth of about 1 degree (2 degrees, whatever) in order to be able to isolate the right satellite on the arc. That's at Ku-down, which is about 11 GHz. A given antenna will get "wider" as you go down in frequency, so the beam width at 2.4 GHz for this same antenna is much wider. I believe the beam width and frequency scale inversely, so if you go down in frequency by about a factor of 5 (11/2.4) then your beamwidth (however you want to measure it) goes up by the same factor.
So your beamwidth at 2.4 GHz is going to be something like 5-10 degrees. And it's not a super sharp rolloff, so you'll find that signal easy.
Another way of expressing all of the above is to say that an antenna with a certain gain at a high frequency (like Ku band) is going to have a lower gain at a lower frequency, and the corollary of that gain reduction is lobe spreading.
Hey, maybe someone here can point us to a visualization tool for this -- looking at an antenna pattern for a given antenna, crank down the frequency and watch the lobes spread out and drop.
One simple rule for its versus it's
I guess that would have been funnier if I knew how to use the intarweb and HTML.
All better!
Look at hack 75!
BiQuad Feed for Primestar Dish.
Imagine a Beowulf cluster of those!
we have a .3 mile setup with two directtv dishes going for the past 3 years. it has worked with very little problems. it doesn't have line of sight, rather it has to go through lots of trees and veggitation. the only maintainence was the plastic I siliconed to the front of the waveguide got brittle and I had to replace it. I replaced it with some thin glass from $1 store picture frame. that should last for a while. also, since the wave guide is aluminum (dryer duct) it wont oxidize.
Anchoring structures by digging holes happens to be my specialty... for a summer job at 15, I dug a 8 foot deep hole with a shovel and post-hole-digger... I had to multi-tier it and it was a pain, but 1/2 ton of concrete and a 30 foot ultility pole later, my gramma get's Norfolk, Va channels in Greenville, NC. (Of course we used a kick ass amp and rotator, but that's not the point). That took a while since 7 of those 8 feet were clay... I put too many hours in that hole, not to mention the fact that it flooded once and 2 rats from a field drowned in it and their rotting carcasses were... rotting. Then this summer (16 years old) I dug 4-3.5' holes to anchor a light aluminum shelter. 1600 lbs. of concrete, 12 lag screws, a box of nails, and 50 pounds of scrap steel rods later, I had a shelter that didn't even think of moving during Isabel. I happen to "over do" some simple things like this for my gramma...
Karma: Good, or bust!
I was looking at the slightly elliptical curve of the dish and it occured to me, the Star Choice dishes (Canadian) are designed to pick up two satellites at once. It could maybe give a wider line of sight if someone modified something like this. I think the feed can would have to be modified for something like this to work. Think something like this might work? or would I be wasting my time?
This guy also posted pictures of inside and airport basestation 2.0
It shows where you plug in the MC-Card Connector antenna
That site was my inspirationg in the begining. Here is a pic of mine: My dish
There is a whole lot of info in the netstumbler threads: netstumbler.com
The FCC doesn't seem to care much about power levels and antennas in the ISM band. Remember, it's kind of a throwback "freebie" given to appease the anarchist crypto parasites and cheap low end consumer equipment for those unable to afford the "protected and scarce" high dollar bands that go up for auction. :-)
The only exception might be certain commercial product vendors who try and sell out of spec equipment to the masses. That is actually worth their time, but some guy with a primestar dish? no way. [ Like linksys getting pressured to take their 2.4Ghz amps off the market because they could interoperate with too many other "unapproved" equipment configurations. Supposedly they can sell them again after making them harder to use with anything but linksys/cisco. arg. ]
There are a number of smaller WISP's that I've come across in the northwest that run 1/2W and 1W amps on their directional point-to-point and point-to-multipoint configurations, but until someone complains that they are interfering, there is no way the FCC is going to proactively come out and bitch.
Wireless users groups across the nation post plans and site configurations using all sorts of unapproved antennas, radios, amplifiers, etc. There is no widespread FCC CRACKDOWN going on. In fact, I challenge anyone to name an incident where a WiFi user (not company) was pressured or forced by the FCC to alter their equipment back into spec. It doesn't happen.
Personally I think this is a good thing. The FCC has done more harm in the 802.11 space than good. Like antenna connectors. Do you know why there is a proliferation of SMA, RP-SMA, N-type, BNC, RP-BNC, MMCX, and any number of other bastardized formats for antennas and equipment? The FCC requires vendors to make their radio's use proprietary connectors to prevent people from easily and usefully extending the range of their equipment with generic antennas. Not that the vendors mind. Nothing like vendor only parts with the associated 400% markup to pad the profit line.
Let the FCC play with the Big Co's and handle licensed spectrum. The ISM bands are where its at.
Wow, I'd hate to see how you'd build a nuclear bomb shelter.
We'd have to devote most of the GNP to build one suitable for a person!
I've got a reasonably fool proof way of making use of these offset dishes, unless of course you're the more talented fool. The Australian Fox TV dishes are similar, but lend themselves to this technique. Aquire some mirrored perspex or something similar. Cut it into small squares, or just steal a mirrorball. Randomly cover the surface of the dish with these using double sided tape. The thinnner the tape, the better. When you reckon you've got enough, point your dish at the sun so that the focal point, your tin can feed or quad, helical whatever is glowing quite well. Too many little mirrors and you'll melt it. All you want is to be certain that the focal point is exactly where it needs to go. Right on the signal feed. If you know where the feed point is, you also know where the sun is. A pointer of some kind pointing directly into the sun, fixed to the dish so that it throws as little shadow as possible can be used to accurately align the dish with little effort. Mount the dish on your roof. sight along your pointer at the source of the signal. Voila. Dish aligned. Jaycar in Australia sell sheets of tiny mirror squares that are perfect for this job. http://www.freenet-antennas.com in WA has managed some big distances with a modified dish. He doesn't use my alignment method thow.
I used to live in a relatively old area of town, and seem to recall seeing gigantic dishes (which, I assume, were used to pick up broadcast signals, or some archaic form of satellite TV...this is all speculation on my part, of course) ... firstly, does anybody else know what I'm talking about, and secondly, would you be able to use one of those? :)
what sort of signal would you get, do you think?
Some links:
KI7cx dish
Primestar dish
Bi-Quad feed for primestar DIY
10 Euro dish with biquad feed
Modifying Confier Antennas for Wireless Networking
More info: Wireless Leiden
you can make one yourself for 2 bucks. Or if you are too lazy to make one, just buy this cantenna for 20 bucks.
I cut the tags off my pillows and the feds didn't come busting in. I also recorded a bunch of NBA games without the express written consent.....
One Bel (10dB) is a power of ten in intensity. The question I have here is, is that a 22db gain over the stock antenna, or is it a 22db gain over a calibrated 50ohm dipole, as most commercial communications antennas are measured? If the former, what is the gain of the stock antenna?
Mnem
"Enough technical gobbledygook. Tell me how we kill this thing."
Or just a wannabe?
... there's always one in every crowd.
..... Obey ..... the .... Rules .....
.... You Must ... We Must .... Obey ....
Sheez
Must
I must
Take your FCC reg printout and your nicest "I'm a narc and I'm special" Deputy Dawg badge down to the truckstop and try busting some truckers. Wear a helmet.
That'll keep ya busy enough to get you outta here since obviously you don't get invited to many parties.
Ah well, no use getting to worked up over some "Downer Dan the Good Samaritan" just making sure we're all "informed" as to our anticipated lawlessness. Maybe Downer Dan can let us know what draconian penalties await. You know, like how many years being gang raped in prison.
Thats ok. The snitch will still be draggin his cross up and down the street, reading his FCC regs like the bible, smug in his holiness when you get out. Just make sure it gets buried with its field strength meter for thats the way it would have wanted it I'm sure.
In the meanwhile don't tell Downer Dan about all the home built computers or screwdriver shop specials missing all those FCC certification stickers. Or how about all those nice pretty puter systems at the big retailers now with the cute window in the side and the purty lites. I wonder if Downer Dan has any fucking idea how much illegal radiation pours out of one of those things. He should. He talks like a man who knows.
Must be hard to sleep at night for Downer Dan what with all those crimminals and their illegal transmissions going right through ole Downer Dans head 24/7. Time to preach some gospel before things git outta hand and ole Downer Dan gits compelled to unplug itself and go save some fetus, up font and personal.
Luckily primestar dishes aren't that hard to find considering that when dish network bought them out, they installed new dishes for everyone often times leaving the old one installed or in the yard of the house where they did the installation.
If anyone remembers BSB, they'll probably think of the "Squarial" 12GHz planar array(I have one of these as a coffee table:), but BSB also distributed a rather cool 30cm offset fed dish which is a good dish for experiments. I have seen these at radio rallies for not a lot. Alternatively the Sky minidishes have to be worth a look.
It has to be bourne in mind when using a dish that the E.R.P(Effective radiated power) is a lot higher than the basic power of your wi-fi card. So you only have 50mW but you get ALL that 50mW focussed in one place. So there are safety issues with using dishes for wi-fi, take care chaps!
Also offset fed dishes are designed to be used with different feed horns from those used on centre fed dishes. Examine a Sky minidish and you will see that the feed horn is oval, like the dish. The reason for this is that you only want the feedhorn to "see" the dish itself, and not a circular patch which includes areas of the wall the dish is mounted on. These areas only contribute noise to the signal and reduce the effectiveness of the antenna.
And finally... I have seen a very effective ku band antenna made from an aluminium wok lid. It had the LNB mounted behind it with a piece of water pipe coming through the middle as waveguide, and a conical reflector mounted in front of the water pipe. So who's going to be the first to mount a USB wi-fi card at the focus of a wok lid then.....?
Oxford Dictionaries Online
Right now, I have the first-generation Starchoice dish -- the circular one -- and for the past few months I have been looking into making it a WLAN antennae myself.
Effectively, from the looks of it, it doesn't matter what the dish's shape it is, as long as the left-to-right width doesn't exceed fifty or sixty centimetres. As long as it meets that width, it doesn't matter if it is a circular or elliptic shape, it really doesn't matter.
Beyond that, I am not too familiar with satellite technologies beyond knowing the encryption on my receivers are hard to crack -- some funky Motorola algorythm that I am not familiar with. Most of these dishes can only receive, but what exactly stops them from sending? Is it a dish limitation, or is it simply the receiver only is programmed to receive and nothing more?
I know they're not as desirable as Primestar dishes, but Dish Network and DirecTV dishes work also. I got a couple for free just by asking. Go to the place that you bought your satellite system from (What, you're on cable? Well, get with it!), and ask. My source said that they occasionally would have a spare dish from an installation, and after a few years in business they had a heap of them in the basement, still in the box. They were more than happy to let me walk out with a couple.
Anyone else read this, and start thinking about the _big_ satellite dishes? We used to have one that was about 6-7 feet in diameter, and that's what I immediately thought of...
Shit, now I'm just making myself feel old.
They shoot looters, don't they?
Most people who've suffered a fire, flood, hurricane, earthquake, etc., don't take too kindly to strangers helping themselves to what remains. They can get quite irrational about it.
quit posting stuff that has been around for years!! i remember reading about using the dish's for antenna's like 2 years ago.
slashdot has lost my interest..
should read "Slashdot, News for want to be nerds so they can catch up and try to talk intelligentally about topics"
blah!
make your own, a little fiberglass, wire screen or aluminum foil, and a calculator to calculate the parabola shape in 3-D....
> a Primestar dish is a little tougher to locate than a Pringles can or a floppy disk.
primestar customers had an option to upgrade to directv.
when the directv installer arrived, i asked him about the primestar dish and "if i could have it".
he said "i could have it"... and that "he had a pile of them he did not know what to do with".
contact your local directv installers and ask.
on another note, (imo) the primestar dish was superior to the directv dish (increased s-units by 20+)... so, i removed the lna from the directv dish and duc taped to the primestar dish. before i did this, i put a pole in the ground, in front of the directv dish, and drew a pencil line for the angle of the lna (used later to help align the converted dish with the audio signal strength level from the directv menu).
it has been there through 2 winters (taped = one of these days i'll fabricate a mount) and my signal strength is still 'pegged' (full scale).
my best, constant, signal strength (sans rain) on the directv dish was +/- 80.
(fwiw) i have been an amateur radio (extra) for >30.
The stock antennas on 802.11 access points are nothing to cheer about; probably on a par with the theoretical "isotropic radiator". I doubt the gain figures would be much different either way.
I have a primestar dish, free to anyone who wants it. I live near Bangor, Maine. Email me, mugwert@adelphia.net to arrange pick up
i failed to mention, i put one of the primestar dishes up, using better hardware for the 801.x portion, and attached it to a 6 foot antenna extension pole (a little over 1 1/2 years ago).
;-)
below that i have connected a video camera in a waterproof housing.
this pole then connects to a 'heavy duty antenna rotator', which sits on top of a 10 foot pole connected to the chimney of my four story city dwelling and is accessible
i get a lot of dx and can observe the area the antenna is pointing.
I used an old PrimeStar dish to catch a falling ceiling. ...or at least most of the wet stuff.
--
"I have also mastered pomposity, even if I do say so myself." -Kryten
should read "Slashdot, News for want to be nerds so they can catch up and try to talk intelligentally about topics"
You must be new here. Welcome!
-Bucky
Me: "I need six satellites, pronto."
SD: "Would that be launched, or unlaunched, sir?"
...that makes it a bit difficult to aim at the horizon (of your own planet).
"A great democracy must be progressive or it will soon cease to be a great democracy." --Theodore Roosevelt
Mmm... But there you're comparing against dBi, while a calibrated dipole will have a greater gain... something like dBi +2.4 dB, I think. Doesn't sound like much, but it does make a difference in comparison to that waveguide/parabolic dish assembly.
Mnem
"So how bout we just stuff this antenna up Darryl's arse and flip the switch? We could watch his eyes cross as a field strength meter..."
I've got a concept for using wi-fi for telemetry on a radio controlled observation airplane, and am wondering at the potential for constructing a phased array antenna for the base station to interact with the aircraft. You can reply to: mlorrey@yahoo.com
"Necessity is the plea for every infringement of human freedom. It is the argument of tyrants; it is the creed of slaves
There aren't that many nuclear bomb shelters because nuclear bombs are able to destroy things fairly easy. Maybe you were thinking of a fallout shelter.
----
---- "Excuse me. Where's the children's gun section?"