JPC-12 Redux

 Yesterday, I wrote about using the JPC-12 antenna for the first time. I had indicated that I had used the antenna on 40m and 30m. I did not bother to tune the coil for the absolute minimum, but instead relied on the KX-3 tuner to touch it up to achieve minimal SWR. It did work very well.

Today, I wanted to try and use this antenna without the internal tuner. I set up the antenna with the coil in the center, between the fixed length elements and the telescopic whip.  So I went off to K-1495 for another activation. I forgot to take the nano-VNA with me. So I had to rely on the KX-3 SWR meter to establish tuning. The tuning was performed at 0.5W. The JPC-12 comes with two marks on the coil one each for 20m and 40m. They are good starting points and I was able to get about 1.3:1 match on both these bands within a few clicks of these marks. With the coil slider somewhere in the middle, got a similar match for 30m band as well. This was the first time I had used this antenna on 20m and got contacts with decent reports from both the coasts. 

Finally, for 17m I had to remove one of the fixed length sections and got a very good match. I was able to work an European station to boot at about 5W. 

To be fair, it was a rainy day and I decided to stick the antenna in a copse of conifers to prevent the antenna from getting wet. Despite, this the antenna performed exceedingly well.

So is this THE POTA antenna? I am increasingly convinced that if it is not THE antenna, it is exceedingly close to being one. 

Update 04 DEC 2023: I took the antenna out again today for activation of K-1522. I used the loading coil and tuned to 20m. The KX-3 read an SWR of about 1.5. Running 5W QRP had a successful activation with decent reports from responding stations. One of these days, I want to do an A/B test of my usual wire antennas against this one. The more I use it the more I like the JPC-12. 

JPC-12 set for 20m

Sidenote: Yes, the parking lot for K-1522 may look a little drab, but this is a park just a few blocks away from downtown Detroit. The GM headquarters is visible toward the left of the image in the background. However, the park it is situated on the beautiful Detroit Riverwalk, voted to be among the top 10 riverwalks in the country. The walk along the river offers views of Windsor, ON, Canada.

If you turn around and look the other way the city and the drabness magically disappear and lush nature beckons along the path!

Park Marker on the Detroit River Walk

 I love activating from this park and Belle Isle State Park, which is about a mile from this location; during peak seasons, it is fun to watch people enjoying themselves here...

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.