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9' Satellite dish turned into Parabolic Listening Device

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raztastik

New Member
Greetings,

Is it possible turn a 9' Satellite dish into a semi long range listening device. I ask this because a neighbor has installed a 9' satellite dish facing our property. The dish is roughly 2000 feet away with an unobstructed view from on top of a hill. The dish is pointed directly out our house. This is a very rural farm area.

They seem to have information regarding our business that no one else knows. We don't use a cordless phone, and have digital cell service out here *no analog calls*.

Any help would be appreciated. Any terms that would be good to google would awesome. Not sure on the exact terminology to search on. Any kits out there that accomplish what I believe they are doing?

Thanks,

Raz
 

EN0

Member
Greetings,

Is it possible turn a 9' Satellite dish into a semi long range listening device. I ask this because a neighbor has installed a 9' satellite dish facing our property. The dish is roughly 2000 feet away with an unobstructed view from on top of a hill. The dish is pointed directly out our house. This is a very rural farm area.

They seem to have information regarding our business that no one else knows. We don't use a cordless phone, and have digital cell service out here *no analog calls*.

Any help would be appreciated. Any terms that would be good to google would awesome. Not sure on the exact terminology to search on. Any kits out there that accomplish what I believe they are doing?

Thanks,

Raz
Yes, this would act like a parabolic reflector that you have seen on flashlights and such. So instead of having sound waves hit the parobolic reflector and bouncing off, this will reflect the wave to a single focal point, in which you would place your microphone. The larger you have the parobolic reflector, the more sensitive it will become, being capable of receiving more sound waves. I've seen several toys in magazines that show that sort of listining device, with a parobolic reflector in the front.
 
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Nigel Goodwin

Super Moderator
Most Helpful Member
A nine foot dish would certainly make a good acoustic collector.

Can you get close to it, it should be obvious if it's got an LNB on the end, or a microphone - and also exactly where it's pointing.
 

picbits

Well-Known Member
You could always counteract with a 9' Satellite dish pointed directly at the neighbours with some nice white noise being beamed directly at it ;)

In fact, you wouldn't even need a 9' dish, just something to make sure the noise is aimed directly at the dish.
 

raztastik

New Member
There is going to be a covert ops soon, to see the actual setup of the dish.

If it was converted into a listening device, then the center focal point would be some form of microphone?

One of the messed up parts of this whole situation is, it used to be our old satellite dish. We upgraded to dish network some time ago, and had sold the old dish to a guy in town. He in turn sold it to the neighbor down the road. We are no means Hillbillies. Though our neighbor down the road has teeth similar to Abe Lincoln.

If we find that this is the case, where he has a listening device setup, is this illegal?
 
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MrDEB

Well-Known Member
counter attack

get a sat dish, local installers have lots as Dishnetwork has gone to a single 20"? dish.
install a white noise generator (a simple 555 circuit) with a mylar speaker mounted at the focal point (where the LNB? is mounted)
this dosn't need to be very loud. mount it away from living quarters like on top of the roof peak. aim at the dish in question.
you now have a narrow beam of sound aimed at this guys dish.
dosn't need to be very loud as the dish will amplify some what the sound.
A parabolic dish will receive as well as transmit (think flashlight parabolic mirror.)
am sure there is a formula for caculating the width of the sound beam at 2000 feet away.
after installing, try an experemint - set up a fake drug deal and see if the police show up!!
 

crutschow

Well-Known Member
Most Helpful Member
Did the 9' dish have a solid or mesh reflector? A mesh reflector wouldn't work very well for sound, unless he has added something to the dish to make it solid.
 

KMoffett

Well-Known Member
I've seen a couple of these set up at a science museum (can't remember where). Opposite sides of a large room. A persons stands at the focal point of one and talks. Another person stands at the focal point of the other and listens. Amazing results even with a whisper. :)

Ken
 

MrDEB

Well-Known Member
does it really matter about mesh parabola

for 2000 feet away?
a solid parabola is best but at 2000 feet a mesh type should work very well.
I still say set up a fake drug deal and see if the cops show up.
If they do then explain about the neighbors listening device.
How did you know that the neighbor knew about company secrets??
Could be a rival company employee?
 

raztastik

New Member
It is a solid dish. Don't think a fake drug deal would spark their interests. They are more interested in whats going on with natural gas wells.

Is it legal for someone to have such a device pointed at another person's business/property?
 

HarveyH42

Banned
Here in the United States, it's tough to figure out what is legal anymore. I'd figure that there is something going on with the dish though, since there isn't much reason for someone to install a large dish anymore. The equipment is kind of expensive to buy, but can be had for free, if you find somebody clearing out a garage. But mostly, there isn't much the dish can receive that isn't scrambled. Since it was your dish, you would know it's worth as such, and should be familiar with what directions it ought to be pointing to pick up a satellite signal.

Get some outdoors type speakers, place them between the house and the dish, enjoy some music, Spanish lesson on tape, The Holy Bible, or anything else. The mike will pick up the loudest (closest) sounds, and should mask or confuse your conversations enough. The volume doesn't have to be annoyingly loud, about the same as your voice.

Might try spreading rumors or misinformation about your neighbor over the speakers, since only. If he's listening, he will of course be asking questions to confirm what he hears, act to control the damaging information. Either way, you would know he's spying.

Get a big telescope, fun looking at the stars, sometimes the neighbors (if she's hot). Or just get some pipe and make something that appears to be one. If the neighbor is listening, then he'll get paranoid if he thinks you are watching...
 

MrDEB

Well-Known Member
Don't think so

they havn't trespassed onto your property phiscally.
I vote to blast em with white noise.
Call your sat dealer and see if they have any leftover dishes that are of no use anymore.
for about $10 you can blast noise their way.
just aim it directly at their dish to cover any concervations you are having.
no need to run it at late night or you could get a hot porno dvd and record the moning and groning. Then the guy would really wonder whats going on in your home---LOL
 

Mr RB

Well-Known Member
They are very directional. They have to be pointed EXACTLY at your house, if it is what you think then it's probably pointed in a window.

Check it out with binoculars etc to see if that is the case, if so, start taking photos and build a case to have them charged for using illegal listening device. I'm sure the local police detectives would be real interested in someone pointing a dish exactly at someones house. Then when that part is over, work out how you are gonna destroy them... Defiling someone's privacy is one of the foulest crimes any human being can commit.

On the other hand, if its pointing above the horizon (ie slightly above your house) its probably just a satellite setup, if I remember right some foriegn channels need a large dish and they point fairly low depending on your latitude.
 

goofeedad

New Member
Just to pipe in my opinion. A few years ago (about 10) I made a decent parabolic listening device with my wifes kitchen strainer and it was only about 10" in diameter. My results weren't great but they were much better than just holding up the mic by itself.

Also, a very good listening device is a laser type, they measure the vibrations on a window or other thin surface but they usually show a red dot (but not always).
 
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tcmtech

Banned
Most Helpful Member
If your fairly far north or south of the equator there are times when a person does in fact have to point their dish nearly level to the ground to get some of the odd satellite feeds.
As a kid one of my friends families had the old style satellite system. When I stayed over at his place there was one station (we were to young to be watching of course):D that had to have the dishes positioning actuator physically removed and then held in place much further up with a clamp in order to get that satellites signal. (his older brothers figured it out)
The dish itself would then point at the horizon in a south/ south west direction.

But being that he is on a hill and if he has it pointed down below the horizon in order to get focused on your place he is snooping in one form or another.

Do you have wireless Internet access? If so he may not be listening to your converstions but rather piggy backing off your connection in order to get free Internet at your expense! :(

And dont let persons looks decieve you. I know some hillbillies that could match wits with any scientist and win!:D
 

H3RB5T

New Member
The reply from TCMTECH is the most likely to be correct. There is really no other explanation for a dish to be pointed DOWNHILL.

It would be pretty easy to find out, if you haven't already, just wait until you think the person is home and using your wireless. Then turn it off and see if they come out to check the dish. Repeat until satisfied (they might not have noticed the first few times or whatever.

I registered just to reply to this thread. I know the thread is old, but the info I'm adding is even more important today. This thread comes up in a number of search results, so I want anyone reading this to know;

A person with no computer skills could connect to another home that is close, with about 30 minutes and some trial and error. In fact, for short distances, just mounting a dish behind your wireless device pointed at the ap while give surprising results.

Using just a parabolic satellite dish it is possible to connect to wireless ap's that thousands of feet and even miles away. For example, using 2 dishes pointed at each other, tests have achieved a full 11mb bandwidth connection on 802.11b wireless over a distance of 22 miles across a desert.

I myself, using just only old DirecTv dish, a wireless dongle, a coffee can, and some hot glue have connected to AP's over 1 mile away from the top of a hill. This is without ANY participation from the target AP at all. It's too easy actually. I'll post some instructions for this antenna, so you can see what I mean:

1. Remove the existing LNB from the dish (the thing on the end of the sick in front of the dish). Note the angle and placement of it.

2. I mount the wireless dongle in the Folger's coffee can (4 inch diameter, 5 1/3 in long). Mount it parallel with bottom can by poking a hole in the side of the can about 2.25 inches from the bottom (for 2.4 ghz wireless). Push the dongle through the hole until it reaches at least the center of the can and secure it with a bit of hot glue. This is actually a crude waveguide antenna that works quite well on its own, if you want to play around with it before mounting it. This can directs the signals that would be wasted traveling in all directions and focuses them all on the dish.

3. Place the can so that opening of the can is facing the dish in the exact same position and angle as the LNB was. The end of the can with the hole is the 'front face'. You are aiming the focal point of the dish at the hole in the can, not the dongle in the can. The front face of the can should mounted be where the front of the LNB was. Mount whatever way you like as long as it doesn't move. Keeping the center of front face of the can in the same place the center of the LNB will improve results, but the arm often prevents this (i eventually cut a chunk of my LNB arm away to achieve this, but it's not required).

4. Point the dish in the direction of the ap you want to connect to.

You must have mostly clear line of site for aps far away but the dish antenna is surprisingly forgiving, as far as obstructions that are very close to the AP like bushes. The dish will work from inside an attic even, if the roof is made of mostly wood.

Also, it might not be just you they are connecting to, even if its pointed right at you. Placing a wireless router with multiple exposed antennas in the right position (just a little closer or further away than LNB's are mounted normally) and using MULTI-LNB dish ( the older, wide, kinda egg shaped ones ) utilizes the multiple focal points and can provide similar access that will canvas a comparatively large area at shorter distances, providing access to entire neighborhoods at once in some cases.

As always the best solution is to secure your router using the latest secure protocols and a strong password.


Cheers!
 
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ronsimpson

Well-Known Member
Most Helpful Member
Using just a parabolic satellite dish it is possible to connect to wireless ap's that thousands of feet and even miles away. For example, using 2 dishes pointed at each other, tests have achieved a full 11mb bandwidth connection on 802.11b wireless over a distance of 22 miles across a desert.
I am getting wireless 5 miles from town.
My renter got kicked off my network (for doing what you think he was doing) and now he used a 9' Satellite dish to steel internet from another neighbor about 1/2 mile away.
Change you security settings and passwords on you wireless router!
 

crutschow

Well-Known Member
Most Helpful Member
A nearly 6 old post resurrected.
Is that a newbie record? :rolleyes:
 
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