Using a Mobile Antenna as a Temporary Base Antenna

For our July Fourth Safety Watch this year, I used my dual-band mobile antenna on a ground plane mount on a camera tripod. I’d purchased a Nagoya GPK-01 NMO Ground Plane Kit ($28) to test my NMO mobile antenna, because my mag mount seemed flaky.

As I was drifting off to sleep one night, I thought that the 1/4-20 screw on my camera tripod might fit the holes on the ground plane kit. It did, so now I have a robust, free-standing, dual-band antenna for em-comm use.

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The antenna is a Comet SBB-5NMO with 3 dB of gain on 2 m. Not a flamethrower, but a solid antenna when used with a good ground plane.

The radials unscrew from the mount, so the ground plane kit packs up small.

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Our station was up on a hill, so we had great line of sight to the whole valley. We ran a mobile rig (Yaesu FT-8900R) at 50 W from a battery, so we had a great signal. We could also hear the other stations clearly, so our station was net control.

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The only thing I’ll change next time is to use 1/4-20 wingnuts instead of regular nuts. I might paint them orange, too. I was sure that I would drop a nut in the grass and never find it.

And yes, that is a classic Gitzo Reporter aluminum tripod. If needed, I could extend the center column to get the radials above eye level.

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Voile Ski Straps

Better than bungee cords! I purchased a few of these, thinking they might work for strapping my fiberglass radio mast to posts and stuff. They are great. Stretchy, adjustable, and super easy to fasten and unfasten. After I tighten a strap, just releasing the tension almost always catches a hole on the buckle to secure it. Lovely design.

Here is one of the two I used to strap my mast to a railing on top of Mt. Umunhum for a SOTA activation. My shortest straps are red and 15 inches long.

Voile 1

Earlier, I used a longer blue one (20 inches) and two of the red ones, linked, to strap the same mast to a walkway post for ARRL Field Day.

Voile 2

A red strap held the balun to the top of the mast to take stress off the connectors.

Voile 3

I started with this variety pack of three sizes ($16.50 at Amazon), then stuck with the same color scheme for ordering more.

I’ll be taking these on every field radio outing. That means I’ll have swap them back and forth between my emcomm go bag and my SOTA gear. I think I can manage that.