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VHF/UHF Antennas

 

VHF/UHF Antennas

Filed in Antennas on Mar.15, 2003

In March of 2003 I decided that I wanted an outdoor antenna system for 2-meters and 70 cm.  I was involved in the Arizona Near Space Research balloon launches, and setting up an echolink link at my house.

I found an article in one of my old Handbooks that described using copper pipe to build a 2-meter J Pole Antenna.  By following the article, it was simple to create an effective antenna for two meters.  For 70 cm, I simply made a 1/4 wave ground plane antenna.

 

2-meter J-Pole

After cutting all of the parts to the required length, taking into account how far they slide into the connectors,  I cleaned the joints, then soldered it all together with flux and plumbing solder.

2-meter J Pole matching section

After soldering everything together, including the sliding matching clamp, I built a really simple 1/4 wave groundplane antenna for 450 mhz.  These were both mounted on a piece of 1-inch copper pipe, which was hoisted to the top part of the tower, just below my cushcraft A3 beam.  It was a warm day, and I got a little exhausted while working up there, so I came down, and my brother Roger, ka0jti, finished clamping everything in place for me.  You can see the 70-cm antenna on the right.

KA0JTI on Tower

And here is the final result.  The 70-cm antenna does amazingly well, easily reaching to my workplace 13 miles away, and covering most of the East Valley without a problem.  It's amazing what 40 feet of elevation will do for you!

Antenna Farm at WB0SMX

And here is a closeup for the VHF/UHF antennas.

2-meter and 70cm antennas

Migrated Comments:

One Response to “VHF/UHF Antennas”

  1. ka0jti Says:
    January 26th, 2009 at 5:56 pm

    Nice site Randy.
    Roger

 

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