The Shack

QRP Mobile: a Shark HamStick installation

Moving has a way of causing you to revisit the recesses of your house. As I was digging around in the closet in my shack, I discovered an abandoned project. Last hamfest I went to, I acquired a mobile antenna mount and some Shark HamSticks for 20, 30, 40 and 80.

I thought: rather than move these, why not install them? So I got to work and got them all mounted up this last weekend.

The Jeep style mount is attached to the tailgate of my truck using 1/8in studs. To ensure good electrical connection, I took my Dremel and sanded the paint off the tailgate where the studs screw down. I also found a good spot to attach a grounding strap from the tailgate to the bed of the truck, again sanding off the paint to ensure a good contact.

The sticks tuned well enough, but I was dissatisfied with the SWR readings on all of them. The best I could manage was 1.8:1 for 20, 30, and 80. On 40, I couldn’t get it down past 2.7:1 so at this point I’m reticent to connect it to my FT-818 or any radio for that matter. Ferrite beads did nothing for the high SWR readings. I can’t locate the antenna in a different location on the truck. I’ll experiment with grounding the entire body to the frame better next to see if this affects performance.

Results were promising whenever I used my FT-818 on the air. On 20m during the late afternoon, the Reverse Beacon Network picked me up after calling CQ once. Conditions were good with an SFI of 118.

30m didn’t do as well immediately but I was spotted. Time will tell if these antennas work well on the lower bands using QRP power. I’m afraid the 80m antenna is little more than a resonant dummy load but I’ve not stuck it on the air to see yet.

Within one day of operating for 30 minutes total, I’ve made two contacts on 20m, one onto a NM SOTA summit and another into OR. So far, I’d say that if I’m able to make contacts, then the antenna works. It never ceases to amaze me what 5 ways can do.

That being said, I believe improvements can be made. I’m hoping that improved grounding will bring the SWR down on all bands, especially 40m. In the future, I might pick up some sticks for the higher bands since Cycle 25 continues to improve.

For a few days this week, I’ve been racking up SOTA chasing points on my lunch break on 20m. I’m not breaking pileups, but I’m getting out to the activators out there.

The setup works, even at QRP levels. That’s what surprises me the most. Compromise antennas can work

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