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2 METER 1/2-WAVE J-POLE
VHF-FM Antenna Made From 450-Ohm LADDER LINE
Great first time J-pole project.  Covers most of the basics.
This small and thin design also makes it good for several stealth applications.
And......We've nicknamed this design the "LL-Coool-J"
Click on these images for more detailed information.

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Comments section
NØLX  Bicycle mobile VHF
http://hometown.aol.com/n0lx/vhfbike.html 

Check out this WebPage with Jake's 2-meter, 5 watt, HT, bike mobile setup.  
He uses a fishing pole to help support his colinear 1/2-wave j-pole.
Several new ideas and great images too!


 
 
I made a 2 meter colinear based on the same design that I later found on your website. I'm a machinist by trade, so I made it from stainless steel and Delryin platic. I thought you might be interested in a pic (attached). I find that it works quite well for FM simplex out to about 60 miles from my base station to a mobile station. It's only up about 17 feet at the feedpoint. I enjoy building antennas and use only homebrew antennas other than a comercial 10 meter antenna I have up. Anyhow, I just thought you might like to see a pic. Take care, Mark/AC7AZ



Hi Mark,

Thanks for checking out the Hampage.  Kim and I have a lot of fun doing this Web project together.

Reengineering j-poles is great stuff.  We did this section on the 2-meter j-pole from 450 ladder-line in hopes to get others interested in building homebrew antennas.  Like the j-pole, this collinear configuration has been around for some time.  450 ladder-line is easy to work with and short cash.  Turns out to be a good product for modeling VHF antennas.  Everyone seems to have a short unused roll of it collecting dust someplace in the shack.  The best idea we came up with was the addition of a so-239 for easy separation of the coax.  Ref:  http://home.comcast.net/~buck0/ll5coolj.html  Works out great this way for portable emergency communications applications.  Not sure if it's truly a new idea?  But, perhaps a new spin for VHF..different and fun..

Your fixed antenna from stainless looks really slick!!  Thank you very much for sending us the image!!  I see you used a coax matching balun in this design.  Interesting stuff!!  Can you please send more info in this balun idea?  Also, is it okay to post this message you sent, and the image on the Hampage?  We will start a new comments section for this.  Totally up to you..  If not, that's okay too.

Thank you!
73,
Steven W. Merrill, KB1DIG
Emergency Coordinator
Amateur Radio Emergency Service
Strafford County, New Hampshire
http://www.w1fz.org/ares
603-749-3170



Hi Steven, Sure you can post the message I sent. I found an online coaxial balun calculator, although I use my analyzer to trim mine to the desired freq. Let me see if I can find it for you. I like to play with antennas. I attached a picture of the colinear Super J-pole antenna I use on my garage station. I also made up several 5/8 wave groundplane antennas that a few of us use mobile here in Phoenix. I haven't found an antenna to beat it yet for mobile use. I'll send a picture of one seperately. I made a big 2-meter corner reflector too, I'll see if I have a pic of it on disc somewhere. Keep in touch, Mark/AC7AZ



Here's the link for the balun calculator and a picture of a 5/8 wave too.
 
Click here: 4:1 coax balun design.



Hi Mark,
 
WOW!!  Great stuff!!
 
Thank you for the quick reply!!
 
I'll save all your contact info and all the images and post something in a week or so.  You could get some e-mail from others intrested in your antenna ideas.  I know we have (not a bad thing).  A lot local happenings now..  Ref: http://www.w1fz.org/ares/k1stf_net.html  This new EC stuff keeps me hopping.  Will send you a message and a shortcut link back, to let you know when it's finished.
 
That's the one things I don't have at this QTH..  an antenna analyzer.  I really need to get me one of those things...;-)  Will help us cut down on the number of project rejects too.  But, for us, it's only wire..hi hi.
 
73,
Steve KB1DIG



Cool beans. By the way, I made the 2 Yagis in the background of the 5/8 wave photo too. Mark.



I hope you're not getting tired of these e-mails, but I found some more pictures I thought you might find interesting on my old computer. I'll send them as a zip file. One is the corner reflector I made for a friend of mine, I used a t-match. Another is a closeup af a hairpin match I used on a six meter antenna I made for another friend. I got the plans from the ARRL Antenna book for that one. And the last one is a closeup of the coil form etc. of a 5/8 wave. I have several of these forms made up and I'd like to send you one to play with. You'll need to get 4 #6-32 nuts for the radials, 1 #10-24 nut for the radiator adjuster, and 2 #8-32 set screws to hold the radiating element in place. I would recommend getting stainless steel, they'll all cost around a nickel each. You'll also need a couple of eylet type solder lugs to attach the coil wire itself to the radiating element adjuster and to the groud radial ring. Than its just a matter of tapping the coil for impedence and trimming it to length for SWR. I tap the coil with the center conductor of the coax at the 4th turn down from the top, and attach the shield to the ground radial ring. That will get you close. I'll see if I can find a long enough tube to ship all of the elements in and get back to you. I assume your address is good on QRZ? Take care, Mark/AC7AZ. 
 



These are some of the iambic paddles I make too. Mark. 
 
 


Hi Mark,

Come to think of it, I read about these exact same paddles you made on eHam.net.  This is art!!  Passion!!!  Truly amazing stuff!!

Thank you very much for sharing these images.

Net time in 30 minutes and I'm doing net ops...got to run..hi hi

Be good!
73,
Steve

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