I've been searching for an easy to deploy HF vertical for quite some time. Although I have a SOTABEAMS 20/40 linked dipole, it is cumbersome to deploy, with the end result being almost always a rat's nest of wires. My MFJ1899T loaded vertical, although convenient, is after all a compromise antenna. My search led me to this antenna, something that costs about 50AUD, shipping included. For such a low price, one cannot be wrong ! I promptly purchased it and left it in my car boot.
On January 27th 2025 evening, I finally decided to test it. I loaded my car with QDX and FT817ND along with a few accessories, and drove to South Perth foreshore. The location is perfect to test a vertical antenna, and also has the same gridsquare as my QTH. Also proximity to Swan river may improve the performance of a vertical antenna. From "touchdown" to key up, it took me about 10 minutes, of which a substantial amount of time was spent fixing a broken Anderson power pole contact. I chose 20m as the operating band. Tuning the antenna was quite easy with nanoVNA, although I had a use a short pigtail to connect the VNA to the antenna. I intend to homebrew a simple BNC jig that would help me calibrate the VNA at the cable end in field conditions. The final lineup was laptop -> QDX -> homebrew SWR meter -> antenna. No tuner was used or required. The deployment can be seen in Figs 1,2 and 3.
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Fig.1. The antenna as deployed. Keen eyes may spot the WACA Ground in the background !
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| Fig.2. The transceiver setup. My homebrew SWR meter can also be seen. |
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Fig.3. A nice way to spend a summer evening ! The only thing missing was a cup of chai :)
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I managed to log 6 FT8 and 1 FT4 contact from this deployment, of which one was to Indonesia and another to Japan. However, the most interesting result was obtained with WSPR. A single round of 20m WSPR yielded 36 spots, which is my personal best. My FT8/FT4/WSPR signals were also getting reported in pskreporter, although I defer the analysis and visualisation with the pskreporter log to a future post.
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Fig.5. A single round of WSPR yielded 36 spots. Not bad !
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Fig.6. The antenna is definitely radiating RF.
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The key takeaway message is that the antenna is definitely working. I also learned a few lessons, listed below.
- Have a sturdy power connection, use a barrel plug to crocodile clips straight cable for QDX.
- No more fiddling with SMA connectors in the field. An OSL BNC jig will help calibrating the nanoVNA at the cable end.
- The radial system needs to be improved as the radial wire included in the package is probably inadequate. A small aluminium plate at the base of the vertical antenna can act as a common connection point, with a few resonant radial wires attached to it.
- Instead of using a Kmart storage box to carry the equipment, use a toolbox style box.
73,
VK6JN
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