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Homemade satellite dish

— Posted by Just0nePepsi on 8:21 pm on Feb. 19, 2002

I saw a homemade satellite dish one time on tv. It looked like a coffee can with some wires and shit hooked up. I wanna try to make one for my shortwave radio. Has anyone tried this or know of any plans. If not I’ll try making one and put up some plans.

— Posted by preditor on 9:13 pm on Feb. 19, 2002

I don’t have the plans but I’ve seenthem before. I found them just by searching for them on a search engine

— Posted by Just0nePepsi on 9:31 pm on Feb. 19, 2002

I tried but I couldn’t find shit.

— Posted by Hergor on 10:37 am on Feb. 20, 2002

i got a book about it in german. guess that doesn’t help much, does it? ¬†ūüôĀ

— Posted by qube on 7:16 pm on Feb. 20, 2002

HAHA aslong as you aint putting them on your house, someones house down my road has a lot of home made looking satelite dishes on his house and it looks a fucking mess.

— Posted by Switchy on 8:12 pm on Feb. 21, 2002

I don’t know how informative this site it, it’s just something from google, but I skimmed it and it’s not in sanskrit or anything.


— Posted by Durf22 on 4:59 pm on Mar. 4, 2002

if any1 fins any shit on the sat thing tell me

— Posted by somefukinsnapov on 7:52 pm on Mar. 4, 2002

yes i was looking for something the same for my radioshck pro 28 but ,zam said in another thread that the satellite thing wont work on scanners unless there is someone else on the other end of th e satellite?? i dunno but that guy seems kinda cluey,

but i was more thinkng along the lines of just a big assed antenna like hella tall with the booster style setup ?! thats where im headed at the moment thought..ill keep my progress posted!

— Posted by Hergor on 3:53 am on Mar. 5, 2002

usually satellite dishes are made to recieve a signal from a satellite.

somefukinsnapov, if there’s nobody sending a signal to that satellite (what the cops surely won’t do – besides then it would be useless to you because it could origin from anywhere in your area/country/continent) you cannot pick up such a signal… what you need is an antenna made of wires/metal-bars…those are better for recieving a signal from the ground because they don’t focus on one spot only but take in the whole frequency spectrum… ūüėČ

— Posted by drybilgeltd on 11:37 pm on Mar. 5, 2002

Satalite dishes have a down converter bolted onto them to convert the microwave signals to a lower frequency that a coax cable can handle without a lot of loss. ¬†The down converter requires DC power to operate. I’ve tinkered a little with the type that is used with ” Direct TV ” and other brands. Depending on what transponder is needed by the control box ( Descrambler ) which of two different DC voltages is fed down the coax cable to operate the LNB converter. The output of television satalite dishes are totaly useless for shortwave radio’s ( also known as High Frequency radio’s). ¬†An antenna I built some time ago that was cheap and dirty but covered from the bottom of the standard broadcast band ( 540 KHZ ) to the 10 meter Amateur band ( 30 MHZ ) was made from 4 pieces of plastic water pipe, a couple hundred feet of wire, some 50 ohm coax cable, a few small DC operated relays ( mounted on the antenna ), a large ferrite ( powderd iron ) toroid for makeing an isolation choke, some capacitors ( to block dc control voltages but pass the radio signals ), a power supply with some switches in a cabinet to control the relays (mounted on the antenna ). Some other stuff like solder, glue, nuts and bolts, rope ( to hold the antenna up straight ) etc. ¬†

 It looked like a 20 foot flag pole when erected. I will post construction details if someone asks about a good multiband disguised antenna. By the way, it worked better than I had hoped for.  

— Posted by somefukinsnapov on 1:58 am on Mar. 6, 2002

fukin cuttin sick drybilge!!1 thats the shit i want ,can u post me the plans,i cant imagine that new thread not being relevant to any topic!! i can see it yet i dont think i can follow on those brief instructions,

BTW i dun only need police frequency ,just any old havin a laugh in my pissant town is few and far between

— Posted by drybilgeltd on 4:36 am on Mar. 8, 2002

Quote: from somefukinsnapov on 5:58 pm on Mar. 5, 2002
fukin cuttin sick drybilge!!1 thats the shit i want ,can u post me the plans,i cant imagine that new thread not being relevant to any topic!! i can see it yet i dont think i can follow on those brief instructions,

BTW i dun only need police frequency ,just any old havin a laugh in my pissant town is few and far between

Justonepepsi asked for an antenna for his shortwave radio and Sumefukinsnapov has shown interest. So here goes the plans. Read each section of construction until you kind of understand what to do before you try to do it, because my instructions may not be in the best sequence. It may take a couple posts to complete it. Did you ever try to put together a Heathkit, or a Radio Shack kit? At least with that you get the parts included.

A little understanding about different radio frequencies and antennas will help. The higher the frequency the shorter the antenna to be resonant ( tuned ). There is a radio term called “Q” which may be defined as quality of goodness. A high Q has sharp tuning or narrow band pass, low Q has wide bandpass. Because of the very wide coverage of this antenna, its electrical length is switched to 7 differant lengths, one of them being a real VHF,UHF or CB antenna at the very top. The low frequencies require a very long wire. Look inside your transister radio and the antenna is made of a powdered iron rod ( ferrite bar ) with a lot of wire wrapped around it. The ferrite bar helps with the magnetic affect to make the antenna look longer than the wire realy is. But because every thing is so small, you do not get much signal.

First thing to get is some plastic water pipe ( PVC ) 3/4inch inside diameter. This will be a little over 1inch in outside diameter. Plastic electrical conduit can be used and is resistant to ultraviolet light from the sun. Do not use pvc central vacuum system pipe. It is very thin and will break like an egg shell. It should be outlawed for use in home construction because it is soo shitty. Wrap about 75 feet of enameled magnet wire ( about #20 guage should do ) evenly over the length of the pipe ( use some thin tape every so often to hold the turns of wire in place ) except for a few inches of pipe at each end to attach plastic pipe couplings. You will need about a foot or so of wire free at each end. Do the same for a second 10 foot length of pipe. A larger size of PVC pipe is used as a protective shell with the coils you made ( wrapped around the 3/4in PVC pipe ) slid down inside. The trick is to test the thickness of your wire wrapped around the smaller pipe and make shure it will fit into the larger pipe.

You may use smaller guage wire to make it fit ( Smaller wire will have a higher guage number, car battery cable is about #4 for example ). But for some hard to explain reason the skinnier the wire the more narrow the band pass of the antenna.

You will need 2 “T” connectors for the larger size of pipe, and 1 pipe cap for the same. For the smaller size of pipe you will need two couplings or 2 “T” connectors and an additional short length ( less than 12 inches ) to be used as a spacer at the bottom of the pipe. Run some 50 ohm cable ( RG58 ) inside both small pipes until it comes out all 4 ends ( one piece through each ). Drill 2 holes through side and near the center of the 3/4inch coupling for the small pipe ( you could grind off the side branch of a 3/4inch “T” connector instead ) and somehow make the coupling or “T” connector fit through the large “T” connector. Feed the RG58 through the holes ( one end from each pipe ). The tricky part is getting the large “T” connector centered over the 3/4inch coupling ( or “T” connector ) and have all the wires come out the side branch of the large “T” connector ( 2 coax and 2 magnet wires). Now slide the large size of pipe over the smaller, the assembly will be about 20 feet long.. Is it starting to look good? You are going to hate me now. Take the pipes apart and use pipe glue that is compatable with your pipe ( check with your plumbing supplier because different pipes use different glue ) to glue the magnet wire inplace all the way down. One thin line on each side of the pipe should do. When dry, reassemble. No glue is needed on the 3/4inch coupling. The upper section of large pipe may be glued to the large “T” connector to keep out rain water but do not glue the bottom pipe to it. The second large “T” connector is used at the bottom with the coax and magnet wires comming out the side branch. ¬†Use another 3/4 “T” with the side branch ground off ) and pull the coax through it and then out the large “T” connector. The outer pipe may need to be shortened an inch or so to make the center of the “T” connectors line up. ¬†Add a short piece of 3/4pipe to make, #1 the coupling at the mid section centered in the “T” connector, and #2 the bottom of the lower “T” connector even with the bottom of the the short section ( this supports the small pipe on the ground when errected ).

The electrical wiring part will be in another post. I will waite a day or so for any questions on this part.


(Edited by drybilgeltd at 1:56 am on Mar. 8, 2002)

— Posted by Just0nePepsi on 11:52 am on Mar. 8, 2002

Well i’ll be damed, you did some good stuff here. You should write this into a text file and give it to Xpl0siv

— Posted by drybilgeltd on 1:01 am on Mar. 9, 2002

Thank you JustOnePepsi!

 Us mad scientist types need a good comment every once in a while so we do not go around doing bad things and hurt nice people.

¬†Here is some info on how the antenna switching works. ¬†At the bottom of the antenna will be some small relays. ¬†This antenna is ment for receiving or maybe have a CB transceiver set ( 5 watt ) connected. ¬†With that understanding, high power relays are not needed. On the coax cable at the bottom of the antenna, we can have ( 1 ) zero volts DC between the shield and center conductor, ( 2 ) positive 12 volts or ( 3 ) negative 12 volts. ¬†this voltage goes all the way up to the top of the first 10 foot section where the coax comes out the side branch of the “T” connector. ¬†If there is zero DC volts on the coax, a relay at this point ( normaly closed contacts ) will make (1) a connection between the shields of the lower coax (using the moving contact ) and upper coax ( Using the stationary contact ), (2) a connection between the center conductors of the lower coax ¬†( using the other moving contact ) and upper coax ( using the second stationary contact ). The relay will be a double pole double throw ¬†( DPDT ). ¬†A second relay will make connection between the lower magnet wire ( using the moving contact ) and upper magnet wire ( using the stationary contact ). ¬†To keep RF signal out of the relay coils, a small choke is put in series with the relay coils. The relay coils are connected to the shield and center conductor of the coax at the top of the lower 10 foot section. Also a diode ( 1 amp most any voltage ) is in series with the relay coils so that only negative voltage will make the relays pull in. What is called a snubber diode is connected across the relay coils in such polarity that the snubber does NOT conduct when the negative voltage on the coax center wire makes the relays activate. The snubber diode is just another 1 amp diode. ¬†The relays still have a couple contacts not used. The relay that is connected to the coax will have the unused stationary shield contact connected to the upper magnet wire. The relay that is connected to the magnet wire will have its unused stationary contact connected to the upper coax shield. The idea here is this, ( 1 ) when no DC is present on the coax, the upper and lower magnet wires are in series, and the upper and lower coax are in series. ( 2 ) when 12 volts negative is present on the coax, the lower magnet wire is cross connected to the upper coax shield, and the lower coax shield is cross connected to the upper magnet wire. When the cross connection is made the upper coax center wire is NOT connected to anything, and the lower coax center wire is only feeding 12 volts DV negative to the relay coils through a small choke and a steering diode ( used as a diode logic ).

 There are 3 more parts to the antenna wiring. (1) the very top of the antenna ( another relay, diodes, rf capacitors, lightning protective voltage dependant resistors and a rf antenna connector known as SO239 ), ( 2 ) bottom of antenna ( more relays, ferrite toroid choke, rf plug and socket connectors PL259 and SO239, terminal strip for multiconductor control cable, wheather protective housing for all this stuff, and ( 3 ) the power supply and control switch. The top and bottom wiring will be the next discussion.

 Very respectfully


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