N4REE - Minimalist Ham

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A Failed antenna experiment

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The Shark HamStick monoband antennas perform fairly well for me. Like all of my “backyard field day” antennas, the downside is that I need to set them up in the morning and bring them in at night. There’s all sorts of wildlife in that wetland behind us and I don’t need a gator or wild pig dragging away my stuff. Although it takes only a few minutes, how about something more permanent?

Idea! One of the hams around here uses a couple of tarheel screwdrivers attached to the structure at the back of his home. That structure has a large metal framework that he uses as a ground plane for the antennas. I don’t have that same sort of structure, but I do have a full surround of rain gutters and the downspouts run into the ground. Hmmmm, wouldn’t they be a good ground plane?

Nope, nada, no way José! As a feasibility test, I took a HamStick up to the gutter, using a WRC base mount, clamped it in place, set a grounding wire from the base to the gutter structure, and tuned it a bit. The best I could get was an SWR of 2.3:1. The tuner in the TR-45L is definitely not happy with that … and the grounded rain gutters are certainly not a ground plane.

A good day for the 20M HamStick

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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!

Wet and Windy

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Unusual for the sunshine state…

We’re on the 2nd day of a significant storm (weather, not solar) that has brought lots of rain and wind. I am not deploying any antennas outside, other than the roof top 20M dipole. During yesterday’s heavy rain, none of my antennas were very happy. In fact, the roof top 20 wouldn’t tune at all on the TR-45L. So, I start today with a lot of SWR testing before even turning on the radio. All on 20M…

Solar conditions were “Active” due to arrival of recent CME bursts. MUF was above 18Mhz.

The antennas all, other than the RT20, were INSIDE the lanai, sitting on a wet Faraday “magic carpet.”

This picture shows a Wolf River Coils “Take It Along” tripod, with center loaded coil sitting on one extension rod and topped with the 102″ whip. This configuration just fits in the lanai, which has a 10′ ceiling.

Yes, there are power lines nearby, Those are 330kV Duke Energy lines. They are far enough away that they don’t cause noticeable QRM.

  • RT20 SWR:1.623 @ 14.040 (Roof Top 20M dipole)
  • WRC/CL1 SWR:1.261 @ 14.040 (Wolf River Coil Center Loaded on 1 extension)
  • HS20-0 SWR:2.333 @ 14.040 (HamStick 20 on WRC tripod with 0 extensions)
  • HS20-1 SWR:1.843 @ 14.040 (HamStick 20 on WRC tripod with 1 extensions)
  • HS20-2 SWR:2.000 @ 14.040 (HamStick 20 on WRC tripod with 2 extensions)
  • HS20-2 SWR:1.16 @ 13.720 (HamStick 20 on WRC tripod with 2 extensions – Freq too low)

I spent about 40 minutes looking for optimum “stinger” length on the 20M HamStick and this is as close as I could get. Outside, sitting above the radial field, the 20M HamStick atop 2 extensions can be tuned to perfection and performs quite well.

With these results for an inside configuration, I chose to use the WRC/CL1. It worked fairly well reaching NE, OK, TX and KY, with stations weakly heard from UT, AR, MN.

A bit later in the evening, the SWR light popped on, indicating the antenna was no longer in tune, usually triggered at 1.6:1. I like to tune antennas so I can work with NO TUNERS. The faraday cloth had dried out, changing the ground conditions. I adjusted the collar a bit to keep the rig happy. This particular WRC configuration presented a double dip.

That double dip happens when the wire from the bottom of the coil to the collar is flared outward.

Rotate the collar around to keep that wire close to the coil and the curve becomes the standard single dip. Yes, the collar may then need to be moved up or down a click to find the best resonant frequency.