One of the more inconspicuous backyard antennas is the Shark HamStick for 20M. It stands on a Wolf River Coils tripod with two 24″ extensions, and then the HamStick. This combination makes it a 1/4 wave 20M vertical that is effectively center loaded, and not tall enough to be seen from the street. If you expand the image, the tip of the antenna can be found just above the rear roof line which is much lower than the peak of the major roof.
Why HamSticks when I already have a perfectly useful Wolf River Coils antenna? Simple: frequency resiliency. When I want to change bands with the WRC, it’s a matter of getting out the NanoVNA and adjusting the coil, and usually adjusting whip length. I like to run as much as possible with NO TUNER. The TR-45L has a tuner that works well, but I’d rather use my meager RF to heat the antenna instead of the tuner. So, I tune the antennas. It’s a procedure that usually takes a few minutes to get right. Instead, a quick change of HamSticks (each already tuned for its band) is substantially faster.
I place this antenna over a bed of radials buried in the grass. There are 18 radials, each about 16 feet. That’s 6 times as many as are shipped with the basic Wolf River Coils antenna system, more than 4 full 20M wavelengths, more than enough according to Callum. That hardware is very basic stuff from any hardware store, 8 angle brackets, screws and nuts, ring terminals, about $8. No need to spend $100+ on something from an antenna company. The wires were held down with plastic “sod spikes” until the grass grew over them (about 3 weeks). The antenna’s tripod base connects to the radials with a simple banana plug.
This afternoon’s Parks On The Air (POTA) hunting resulted in contacts from NY to Oregon, all on 5 watts from my Penntek TR-45L. Pretty good day!
Update – best configuration
There are as many ways to configure HamSticks as there are imaginative hams. While originally intended for vehicles, we see HamSticks in many uses other than mobile.
The configuration shown above has things stacked up from the ground in this order:
- buried radial field
- Wolf River Coils aluminum tripod, clipped to the radials via a banana plug
- Two 24 inch aluminum extensions (again, WRC parts)
- The Shark 20M HamStick with the “stinger” tuned for the best SWR at 14.06 Mhz
Now, what if I removed one of those extensions? Can I get a better SWR? Yes, definitely!
- The version with 2 extensions, stinger length 18 1/2 inches, has an SWR of 1.411 with 34.76-J1.12Ω impedance.
- The version with 1 extension, stinger length 22 3/4 inches, has an SWR of 1.087 with 54.15-J1.25Ω impedance, clearly BETTER, and the transceiver is happier too. …BEST…
A WSPR run shows spots across the US to the west coast, north to British Columbia in Canada, south to Panama, and east to the Canary Islands. More on WSPR in another post.
Of course, the next question is, what about no extensions … with the HamStick directly on the tripod?
- The version with no extensions, stinger length 26 9/16 inches, has an SWR of 1.24 with 61.1+J5.0Ω impedance, better than the 2 extension version, but not the best.
UPDATE – May 6 2024 – I’ve been running the 20M HamStick for some time directly atop the WRC tripod attached to the radial field. The NanoVNA consistently reports that configuration as having 1.02 to 1.04 SWR. BEST YET!
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