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Last Saturday

It was a good thing I had all the parts ready. Jason, Meredith, Bob, and I had 5 hours to build a quad directional antenna before the t-hunt. Finally, it is finished! Time to hook it up.

Jason hooking up the ICOM-2200H 2-Meter Radio to the quad antenna.

A T-hunt is where ham radio operators try to find transmitters that are hidden (in our case anywhere in the Inland Empire). The transmitters typically send out a brief signal every 10 minutes. The first step for us was to build a quad– a directional antenna. It has four elements. Two directors, the driven element, and the reflector–and mount it on my car.

Me inspecting Jason’s through the sunroof mount. It looks good Jason!
Meredith, Bob, and I calculated the element sizes for the best pickup on 146.565MHz while Jason used advanced math to cut out a perfect moonroof from plywood. The basic principle is to spin the quad around when we hear a signal–while watching the s-meter. Where the signal is strongest, that’s the direction the transmitter…

Looks like we’re finished. Lets do a road test! (notice the cool flaming hood?)

Our first road test was on the freeway heading to the starting point. 45, 55, 65….it’s holding together! I didn’t realize the amount of attention you get when you have one of these on the roof of your car. The kids were waving at us, while cruising around the neighborhoods we hear the “what the **** is that thing?” …and every once in awhile someone will call the police on us thinking we’re a ufo. The police know who we are–we have FCC licenses to do this. |:-)


“Off you go boys! Good luck hunting!” — the girls.

Meredith was the spinner, I drove, Jason handled radio #2 and the attenuation, Bob calculated the intervals between signals so we could be at a high spot whenever the transmitter went off.

This was our first hunt as a team. We found both transmitters without any help from the other hunters!

Much thanks goes to Jon and Jim who took me on their hunts and trained me, and thanks to the guy who drilled the holes in the boom for us.