This is my first year of POTA, I started early spring and settled on using a random wire antenna for my activations. This served me well for all these months. But, with winter approaching, the Michigan parks are moving all the picnic tables into storage. With snowfalls imminent, all I may have access to is the parking lots. This makes finding a convenient tree and getting the wire up on it a little cumbersome. I used to have a Eurocom vertical, but setting it up involved cinching multiple hose clamps. Further, it is also much heavier and the sections did not reliably stay up. Getting the antenna into the same configuration multiple times was also proving to be difficult. After a quick survey, I found that many activators were using the JPC-12 vertical successfully. It had the right form factor and weight, which meant, I could use this antenna on the trails during summer and during my motorcycle based activations.
I got the antenna a few weeks ago, but work meant, I could not get out to a park to test it out. I did testing with nano VNA and found the approximate detents for various frequencies. I did not require the lowest match. I wanted to get it pretty close and let the KX-3 antenna tuner touch it up. I finally got to take it out for a spin today. However, I can confirm you can get close to 1:1 to 1:1.2 match on at least the 40m, 30m, and 20m bands.
The antenna comes with four fixed length sections that screw together, a telescopic whip, a tuning coil , SO-239 connector section, some radials (long ribbon data cables that can be split if needed) and a ground spike. All the screw connectors are M-10 which makes other mounting options possible. I went with the standard configuration of having the coil in the middle between the fixed length elements and the telescoping whip. I was concerned that it might take a little longer to set up and tear down compared to the wire up the tree, but I think with a little practice, I can easily put this antenna up in about the same time.
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| JPC-12 in a functional carry bag. |
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| JPC-12 debut at K-1518 |
So how does it perform? Exceedingly well. I worked 40m and 30m this morning and found the reception exceedingly good. The noise was pretty low. I made about 45 contacts running about 5W; the contacts gave me decent signal reports . I was surprised with the number of close contacts I worked; I was expecting a low take-off angle might prevent that. I could not try other bands as they did not seem to be open in the early morning hours when I was activating.
The advantages
- Quality construction
- Light weight
- Quick setup
- Resonant on 40m, 30m, and 20m without a configuration change (except for tuning coil adjustment)
- Power handling up to 100W
- Can be used as a mast in a pinch.
- Bands other than above will need removal of elements or adjusting whip height
- No guying solution provided; may not need one unless extremely windy.
Update: 2024/01/10 - I experienced the first failure of the antenna component. The extensible whip fell apart. It is to be noted that I have been using the whip for about 30 activations. I also left the whip stored in my car with temperatures well below freezing. I have also been extending the whip in icy and windy conditions with temperatures in the 20F range (-7 C). I am not sure if that is a contributory factor. I have a replacement whip on order from a Chinese website. I still believe that this is a great antenna; it may not be built for extreme conditions but with proper care, it should last a long time.
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