We've seen a few complicated DIY antenna projects before, but we've yet to come across one that makes building one so easy. MAKE has hosted up an eight minute tutorial on crafting your very own short to medium range OTA antenna using just a block of wood, a few spare screws, a handful of old wire coat hangers and a few general tools that are surely collecting dust in your garage. Seriously, it's almost too simple. Head past the break for a look at the video.
Best do it yourself project ever. What kills me is that it probably works way better then anything you can by in the store unless you want to spend a $100+. Awesome.
The problem with his demo is that the test antenna he uses is a VHF antenna, while the antenna he builds is a UHF antenna. So his "bad" reception with the original antenna could have just been b/c there are no digital VHF stations in his area.
Also I don't think he would get good vhf reception with his coat hanger antenna. Which means if any Digital stations are switching back to vhf after the cutover (if it ever happens), this antenna may not work for them.
The only problem is the DIY version lacks the "cage" or wire "wall" behind the bow-ties that the retail versions have. I don't know the exact purpose of it, but I'm guessing it helps with rejecting off-axis signals and reflections, which makes an antenna much more effective.
Also... The retail version is only $40+s&h... so watch out how much you spend on this project... I'll do it just because it looks fun, but financially it's not going to save you much. http://www.starkelectronic.com/uhf.htm (first antenna on that page is basically the same as the one in this project)
This same design has been on the internet for years. I made one myself about 6 months ago and it really does work. All channels have between a signal strength level of 92-100 for me. The total cost for me to make it? $7.00
This 4 fan-dipole pairs (4 bowties) antenna is a DB4, a (badly done) clone of the commercial one we won't name here. The antenna, when done correctly is the second to best UHF antenna you cam make. The model showed here has the following problems:
a) the long vertical wires (phasing lines) are not evenly spaced. They should at all time, including the crossover, be at 1.25 inch from each other.
b) the phasing lines should not be right against the wood board as it changes the electric field property around. There should be at least a 1" standoff under all 5 pairs of screws to rais the phasing lines in mid air. This should simplify also the crossover twist in mid air, in case you were wondering!
c) the whiskers length is supposed to be 9-10 inch, not 7 or 8.
d) the spacing between the whiskers pair is supposed to be 8.5-9.5 inches
e) the voltage 4:1 balun transformer AND the coax cable should go away from the antenna plane toward the back. One simple way to solve that is to drill a hole in the wood board about 1" below the center screws (and standoff), to pass the balun body through. You can lock the balun in the hole the way you prefer, splice of wood, hotglue gun, etc...
f) you very likely will want a 11th screw, a longer one, to pin a flat base to your mast, so the antenna stands by itself and can be oriented. Otherwise whiskers tips will scratch whatever is around (or worst, the sharp coathanger rods could enter the air vents of any surrounding equipment).
I wrote too fast about point F. I assumed a simpler setup. The steel mast and ties are not necessary and you can avoid those materials. I meant that you can simply screw the wood board directly to the mast. You may want to drill a hole half of the diameter of your long screw so you don't crack the wood mast along its length.
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posted Jan 27th 2009 10:08PM
Best do it yourself project ever. What kills me is that it probably works way better then anything you can by in the store unless you want to spend a $100+.
Awesome.
D'Oh! buy not by...
The problem with his demo is that the test antenna he uses is a VHF antenna, while the antenna he builds is a UHF antenna. So his "bad" reception with the original antenna could have just been b/c there are no digital VHF stations in his area.
Also I don't think he would get good vhf reception with his coat hanger antenna. Which means if any Digital stations are switching back to vhf after the cutover (if it ever happens), this antenna may not work for them.
Noticed that also. Wonder if he knows...
Uhh, that's a VHF/UHF indoor antenna. Watch the video again, the UHF loop is clearly visible.
A good friend made one of these a while back and loves it.
The only problem is the DIY version lacks the "cage" or wire "wall" behind the bow-ties that the retail versions have. I don't know the exact purpose of it, but I'm guessing it helps with rejecting off-axis signals and reflections, which makes an antenna much more effective.
Also... The retail version is only $40+s&h... so watch out how much you spend on this project... I'll do it just because it looks fun, but financially it's not going to save you much.
http://www.starkelectronic.com/uhf.htm (first antenna on that page is basically the same as the one in this project)
This same design has been on the internet for years. I made one myself about 6 months ago and it really does work. All channels have between a signal strength level of 92-100 for me. The total cost for me to make it? $7.00
This 4 fan-dipole pairs (4 bowties) antenna is a DB4, a (badly done) clone of the commercial one we won't name here. The antenna, when done correctly is the second to best UHF antenna you cam make. The model showed here has the following problems:
a) the long vertical wires (phasing lines) are not evenly spaced. They should at all time, including the crossover, be at 1.25 inch from each other.
b) the phasing lines should not be right against the wood board as it changes the electric field property around. There should be at least a 1" standoff under all 5 pairs of screws to rais the phasing lines in mid air. This should simplify also the crossover twist in mid air, in case you were wondering!
c) the whiskers length is supposed to be 9-10 inch, not 7 or 8.
d) the spacing between the whiskers pair is supposed to be 8.5-9.5 inches
e) the voltage 4:1 balun transformer AND the coax cable should go away from the antenna plane toward the back. One simple way to solve that is to drill a hole in the wood board about 1" below the center screws (and standoff), to pass the balun body through. You can lock the balun in the hole the way you prefer, splice of wood, hotglue gun, etc...
f) you very likely will want a 11th screw, a longer one, to pin a flat base to your mast, so the antenna stands by itself and can be oriented. Otherwise whiskers tips will scratch whatever is around (or worst, the sharp coathanger rods could enter the air vents of any surrounding equipment).
I wrote too fast about point F. I assumed a simpler setup. The steel mast and ties are not necessary and you can avoid those materials. I meant that you can simply screw the wood board directly to the mast. You may want to drill a hole half of the diameter of your long screw so you don't crack the wood mast along its length.
a very good gesture,he looks sincere and honest in what he is doing---keep it up! I will try making one--will report the results