Saturday, 10 January, 2004

Tuning the antenna

Tom Whiteside, N5TW, one of the members of the local amateur radio club, offered to check out the antenna I made a couple of months ago (November 10, 2003).  I went out to his place with my antenna this morning, and he hooked up his antenna analyzer.  It wasn't pretty.  The antenna was resonating at about 134 MHz, and was just terrible at 144 and above where the amateur 2 meter band is.  We spent some time trimming and otherwise fiddling with the thing, and finally got it tuned to the right frequency range.  I can now hit the local repeater from inside my garage using only 0.5 watts.  Previously, I had to have the radio on its 5 watt setting in order to reliably hit the repeater.

I learned two valuable lessons about antennas.  First, even a poorly-tuned antenna is better than the little "rubber duck" antenna that comes with the hand-held.  Second, a well-tuned antenna is a thing of beauty.  Okay, three lessons:  an antenna analyzer is a good investment if you're building antennas.  Since Ill be home brewing a few, I'll probably pick up one of those analyzers.

Tom, by the way, has quite the amateur radio setup:  four towers each 150 feet tall and containing a total of about 30 antennas.  He has "Beverage" antennas for 160 meters (just above the AM broadcast band) scattered just above the ground, giving reception that is nothing short of astounding.  His shack (one room in the house) is full of radios and gear to control the antenna arrays.  There's quite a lot of stuff there, most of which I just barely understand.

Fortunately, you don't need all that equipment and those big towers to enjoy ham radio.  It's quite possible to contact stations around the world using a very modest station and small almost invisible antennas.  That's the kind of station I'll be building at home, but it's good to see other stations to get an idea of what works.  I'm looking forward to getting started.