Wanting to build my own antenna

[halfwatt959]

Howdy folks. I want to build my own base antenna just to do it. I don't expect any miracles, in fact failure on the first few tries. That said this is what I'm thinking: copper pipe in progressive sizes so they slide into each other for adjustment purposes with 4 ground radials of 3/8 copper pipe at 1/4 wave length set at 45-60 degrees. I'm currently undecided as to how to construct the gamma match. I also thought I would clear coat the whole thing to resist corrosion. Is the clear coat a bad idea? Is the whole project a bad idea? Was planning on 5/8 wave length since Ive benn informed that a full wave would have too steep of a radiation patern to be effective for practicle communication use. I am planning on using a choke at the feed point. Is this just dumb or is it semi-solid planning. There is nothing wrong with my Mako v5/8 I just want to make my own. Any help, advice and or tutoring will be greatly appreciated. Like I said I don't expect spectacular results or to reinvent the wheel just well just that I want to build my own junk. Thanks again 73s

[Tallman]

The ARRL handbook has information for designing antennas. A vertical 5/8 wave made from copper would be expensive and hard to keep working due to corrosion. However if you went that way a light tin coat would help. There are ways to put tin coating on copper without hot dipping. Electro-less tin plating is one way.
Aluminum tubing would be best, but that's just my opinion.
The best antenna for skip shooting is a long wire horizontal. Once the signal bounces the polarity is ambiguous any way. Great for skip, not so good for local talking though. There is a lot less EMI on the Horizontal orientation.

[halfwatt959]

Thanks for the input Tman. Aluminium would probably be better as you said but I cant get it from the local stores like lowes or home depot. That's the main reason for copper. It is readily available. However if I can find it online I will go with aluminuim . Just an experiment not spectacular results expected just want to say "I built it" Thanks again 73s Karl

[Tallman]

http://www.speedymetals.com/c-8342-aluminum.aspx
The copper would be heavy and hard to mount up.
Certain ham vertical multiple band antennas are simply long wires supported by fiberglass or plastic tubing.

I made a CB ground plane from 1/2" conduit worked pretty good till a big storm knocked it down.

[BOOTY MONSTER]

to use a gamma on a 5/8 you'll need to ad some length to the vertical without making it longer , aka coils , loops , tophat . the gamma will tune a 1/4 wave or a 3/4 wave vertical but not a 5/8 or a 1/2 wave . thats what wolf did on his .

http://www.wolfradio.com/p64.htm



the gamma is for fine tuning on the wolf . you can also skip a matching network all together and add a large coil at the bottom and tap it for length like sirio did on one of their antennas . it's a open circuit antenna with no DC tap to ground .



when i made my 5/8 antennas i tried the tapped maco loop matching network and a tapped coil type ... i liked the maco loop type better . i had slightly better performance with the loop over the coil , but it could have been conditions because i didn't compare them on the same day . the loop was easier to make too . here they are .

[BOOTY MONSTER]

had to break up my reply because i had too many pics .

heres the electrical image of the maco loop type matcher .



a cheap easy ground plane for testing or till you make something better is using four 108 inch copper wires on a PVC X below the antenna . i used two 10 ft sections cut in half with a PVC 4-way holding it together and ziptied to the mast .



copper is a slightly better electrical conductor than aluminum , but the difference is un-noticable on RF using human ears . special high tech equipment can detect a difference but human ears never will . and as already said copper is very heavy compared to aluminum . on a 22 1/2 ft. or longer vertical i'd be afraid it would snap due to it's own weight when raising it or with high wind loads . it will also oxidize very quickly and will not play as nice with aluminum or stainless steel (electrolytic corrosion) . aluminum to stainless/nickel aluminum is much much better .

you can use PEX refrigerator water line for a insulator in a gamma if you have to have a gamma match , but the tapped coil or loop is much easier than putting coils/toops/top hats on the vertical or finding the exact length on the sirio type open circuit with a coil on the bottom . and the loss difference between the tapped or open circuit antenna wont be a issue .

and don't be concerned about DC grounded (closed circuit antennas) myths .

http://www.iceradioproducts.com/80.html

when you want to step up to the best omni available ..... homebrew a beefy sirio vector 4000 antenna ... that's what i ended up doing

[Tallman]

copper is a slightly better electrical conductor than aluminum , but the difference is un-noticable on RF using human ears . special high tech equipment can detect a difference but human ears never will .

I agree totally with everything you said. I was misinformed about copper vs aluminum by a trusted source. Aluminum has less conductivity than copper. What I had been told was "The only reason copper wins over aluminum is the ease of connection using solder." I never questioned the "Trusted Source."
There bits and pieces of mobile antennas that could be adapted for tuning a base. http://www.hyelectronics.com/X-Terminator/products/41/

[BOOTY MONSTER]

you can make your own coil too .

[BOOTY MONSTER]

BTW , here's my best homebrewed antenna .



i ordered all my aluminum tubing from DX Engineering

http://www.dxengineering.com/search/...rder=Ascending

made each order over the phone , everything went smoothly and arrived in 5 or less shipping days and was nicely packaged . i'll definitely order from them again if i need something they sell

[ARCHBISHOP]

Hello booty great antenna design On another forum now ( closed ) a member built built bootys antenna an had great results.