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5 CommentsVirginia, USA
Vegan, animal lover, enjoys the beach, avid reader, wrestling fan, recovering geek
  • How to make a fractal antenna for HDTV / DTV plus more on the cheap

    A few more things to note that will help:1. I like to use PVC pipe in my builds. The reason being is it's cheap, it can be bent if needed by a heat gun or even a hair dryer in a pinch, and is non conductive.2. A hot glue gun is a nice to have when putting things together. I believe screws that hold down aerials change the way the signal is captured for it adds metal to the shape of the aerial. In my last build I used the hot glue gun to glue my connections together. This worked really well. I did an experimental build with cardboard to see how this would work and I was really pleased with the results. 3. Line of site is best when positioning your antenna. 4. Use high quality coax and pick the best for the job. Look here on what to select: http://forums.solidsignal.com/showthread.php/505...see more »A few more things to note that will help:1. I like to use PVC pipe in my builds. The reason being is it's cheap, it can be bent if needed by a heat gun or even a hair dryer in a pinch, and is non conductive.2. A hot glue gun is a nice to have when putting things together. I believe screws that hold down aerials change the way the signal is captured for it adds metal to the shape of the aerial. In my last build I used the hot glue gun to glue my connections together. This worked really well. I did an experimental build with cardboard to see how this would work and I was really pleased with the results. 3. Line of site is best when positioning your antenna. 4. Use high quality coax and pick the best for the job. Look here on what to select: http://forums.solidsignal.com/showthread.php/505-C...5. Signal strength monitor - I have a USB digital TV adapter for my laptop. There is software you can use with them to measure signal strength. For example this one: http://www.hauppauge.com/site/support/support_digi...6. if you have old RG-59 coax and you have a mess of wires in the back of your TV, this will cause a loss of signal due to noise the other wires generate. 7. Dimmer switches that are on the same circuit as the TV are big causes of signal noise and can cause a lose of signal for the antenna. 8. When hooking up the impedance matching transformer to your antenna, it is best to have it at a 90 degree angle to the vertical plane of the antenna (put it in horizontal, having it go straight back ) so that when the coax cable is connected to it the coax is well away from the aerials. Otherwise you run the risk of the coax interfering with the aerials capturing the broadcast signal. You will see this setup on pretty much every store bought antenna. 9. As I said in my other post - you can combine antennas just as long as the coax from each antenna to the junction point is the same length. If you need to build several directional antennas to capture weak signals from distance towers - make sure the antennas are at least 2 feet apart when it comes to the reflector on the antenna. You may be able to put them closer but at the time of this writing I have not tested this. I plan to see if I can build a long range antenna to test. Should be fun. 10. The coax will require a 7/16 wrench. Make sure you have two wrenches. 11. Before hooking to the TV, look to see if the coax plug on the TV has a capture nut on it. If yes, make sure it is snug but DO NOT OVER TIGHTEN. You will break the plug if you over tighten. If you break it you may be able to solder a replacement connection but most likely you will have to replace the board the connector is soldered to inside the TV. (Been there, got the t-shirt - did it on my booster)12. If you are a old gamer like me you may have a NES. The NES coax connector will cause a lose of signal. I even tried a booster to get around that. Nope. You have to hook up the NES using the RCA connectors. 13. I tried using a jig to bend the wire when making an aerial. I found it made for round corners that needed to be tweaked and it made the straight sections not so straight. 14. Some folks will let the aerials be free standing in that they are only connected at the joining wire point. You "can" do this but be warned - if the angles of the bends in the aerials change at all you WILL lose signal. In my builds I like to draw the pattern on the backing material that the aerial is attached to and use my glue gun to make sure the aerial is exactly in the right place. This makes a huge difference in my opinion in signal gain. 15. Aerial stack - in some long rang antennas I've seen a stack of small aerials in front of a reflector. I plan to use this concept in a future build to see if a fractal setup in a stack in front of a reflector would bring in weak signals better without a booster.

    Here is a pic of my experimental build with cardboard and the use of a glue gun. You will notice a few things that I did and may have an impact on my build:1. For the joining wires - I did a "V" type joint. My thinking was I get a higher point of contact with the aerial. The downside is I'm not connected at the end point of the aerial but 3/8 to 1/2 inch on each side of the aerial. This may have no impact, may give me more or may give me less signal. This has to be tested.2. The crossing points for the joining wires - there is a 1/2 gap between the white and black wire. I used 14 gauge electrical wire for it is flexable enough to use and is strong enough to hold it's shape. 3. I pinned down each aerial with the glue gun to keep the aerials in place.4. The impedance matching tr...see more »Here is a pic of my experimental build with cardboard and the use of a glue gun. You will notice a few things that I did and may have an impact on my build:1. For the joining wires - I did a "V" type joint. My thinking was I get a higher point of contact with the aerial. The downside is I'm not connected at the end point of the aerial but 3/8 to 1/2 inch on each side of the aerial. This may have no impact, may give me more or may give me less signal. This has to be tested.2. The crossing points for the joining wires - there is a 1/2 gap between the white and black wire. I used 14 gauge electrical wire for it is flexable enough to use and is strong enough to hold it's shape. 3. I pinned down each aerial with the glue gun to keep the aerials in place.4. The impedance matching transformer is on the backside of the board to help prevent interferance.

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  • How to make a fractal antenna for HDTV / DTV plus more on the cheap

    I've been reading everything in this thread and I've learned a few things that will help:1. When making the bends in the wire for the aerials - the corners need to be sharp as possible. Rounded bends in the fractal aerial reduce signal.2. In between each bend for the wire for the aerials - the wire needs to be as straight as possible. - this increases signal.3. You CAN combine several antennas together to increase signal. The things to remember is the wires coming from the different antennas need to be the same length to the junction point. Otherwise you get ghosting. I have a 4 antenna setup for my living room TV that works perfectly using this principle. 4. The cable length from the antenna should NOT have bends in it if at all possible. Any bends cause a loss of signal.5. The cable l...see more »I've been reading everything in this thread and I've learned a few things that will help:1. When making the bends in the wire for the aerials - the corners need to be sharp as possible. Rounded bends in the fractal aerial reduce signal.2. In between each bend for the wire for the aerials - the wire needs to be as straight as possible. - this increases signal.3. You CAN combine several antennas together to increase signal. The things to remember is the wires coming from the different antennas need to be the same length to the junction point. Otherwise you get ghosting. I have a 4 antenna setup for my living room TV that works perfectly using this principle. 4. The cable length from the antenna should NOT have bends in it if at all possible. Any bends cause a loss of signal.5. The cable length from the antenna to the TV should be as short as possible. Longer cable equals more signal loss.6. It is possible to make a fractal aerial setup omni-directional. In a 4 pair fractal setup - I took and pivoted each pair in the stack by 15 degrees. I then combined several antennas together so I had fractal pairs pointing in every direction. This setup worked extremely well.7. The higher the antenna, the more signal you get but only to a point and then only diminishing returns on any further gains.8. If you use a antenna that is outside - it is critical the antenna is grounded and has a surge protector to protect from lightening strikes.9. Home run (one continuous line) the line from the antenna to the TV if possible. Each additional junction, even a barrel connector will cause a loss of signal.10. Elbow connectors - they cause a loss of signal. I've tried a couple of brands and they all caused a loss of signal.11. Anything metal usually deflects and reflects signal. Things in your home like wires in the walls, appliances, duct work - they all will change the way the signal reaches the antenna or block it. 12. Don't use cardboard in making an antenna. It will seem to work well at first but the cardboard is really just paper and sooner or later - the cardboard will warp. I discovered this with an antenna I made and put in my attic. It was warped something terrible after only a few days.13. Spend the money on quality coax connectors. The cheap ones are simply that cheap and you lose signal. Harbor freight sells a crimper for the quality coax connectors that is around 20$. That may seem a lot but I've seen them go for much more. They also throw in a few coax connectors in the box and they normally got for about a dollar a piece.14. Do the math on figuring out the best type of fractal antenna will work for you. Look at the channels you should get, and how far away they are from you. The links on this thread on doing this are very helpful.15. For the wires that link the Fractal aerials and if they cross (in a 4 pair setup for example) - there HAS to be a 1/2 gap where the wires cross. Put in a spacer so the wires stay apart. You will notice on the impedance matching transformer 300 ohm to 75 ohm the two wires coming out of it have a gap between them. That is there for a reason. If they get closer together - you lose signal. With all the things above and if you are careful - you will build an antenna that will give you a much higher signal than one that is poorly made. I've made about a dozen antennas now and I'm finding doing all these little things add up in getting more channels, more stable signal, and less messing with having to do things like rotating the antenna to pick up the channel you want.Happy building!

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