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Home Brewed Antenna

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Skypilot007

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Dec 26, 2005
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Medford, NJ
I can't remember where I found this link http://wireless.gumph.org/articles/homemadeomni.html to this project. But with a rainy day yesterday and having all the materials around I set up the work bench and built this antenna tuned for 506MHz. The only differences were to recalculate for 506MHz and for using 9913 cable.

Only trouble I had during the build was the 9913 cable. It has an aluminum sheild and its a little hard to solder to but if you tin it before you solder the sections together it works ok. To do it again I would get coax with a cooper sheild. It took me about 4 hours total to build it though I could do it much faster now that I've worked the bugs out of the assembly.

I tested it in my attic last night after finishing it and it worked very well from there. I put it up on the roof today. Its about 40-45ft high now and it works execellent. I have a Comet GP-6 up there also at about 55ft and the homebrewed antenna works equal or better on most distant repeaters I compared in the 500MHz range. I know the Comet is tuned for 440MHz but it receives quite well at 500MHz and that's all I really use it for.

I was wondering if anyone would know how to re-arange this design to make it a dual bander for VHF hi/UHF or 500/860MHz would be neat. Also was wondering if this design could be used to make a 1/4 antenna for lower frequencies, so it's not so tall. Not sure how to re-calculate using the formula for the design. Also was curoius about the bandwidth of this design using 9913 cable for the elements.

Sorry for no pics. I got half way done the thing before I thought of it and the batteries were dead in one camera and the other one was MIA somewhere??? The assembly would look just like the project on the web page except longer sections. I stuffed it into a 9ft section of 3/4" white PVC pipe with a cap on the top. I'll get a pic of it up on its mast tomorrow. It looks nice up there.
 

k9rzz

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Joined
Dec 12, 2005
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3,162
Location
Milwaukee, WI
Nifty little antenna.

Sorry, that's a one band antenna ... not that you can't receive other frequencies with it, but it has resonance in just one band.

Can you load it up as a VHF quarter wave? Hmmmm ... it might ... try it! YOu could get it close I bet.

Would be simple to try if you can get your hands on someone's antenna analyzer to borrow.

John K9RZZ
 

Skypilot007

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Dec 26, 2005
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Location
Medford, NJ
I got a pic of the antenna today. Its working well everywhere in the UHF band for receive from 440-510. I haven't tried it on other bands yet just too see what will happen. I'm pretty happy with it. Total cost was less than $8.00 but I had the coax and connectors laying around.
 

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