❌

Normal view

There are new articles available, click to refresh the page.
Before yesterdayMain stream

POTA: QSO video, antenna update, 20-meter noise

By: Dan KB6NU
2 July 2024 at 18:53

Yesterday, I operated from the Silver Lake Day Use Area of US-3322, Pinckney State Recreation Area. This is a great park, and in many respects, I like it a lot more than US-3315, Island Lake Recreation Area. It’s just a little further from my house than Island Lake, and I think I’ll be spending more time at US-3322, now that I’ve hit 1,000 QSOs at US-3315.

One of the 40 contacts I made was with Jim, N4JAW. He’s not only a very active POTA operator, but also very active on Mastodon. Yesterday, after I returned home, I was pleasantly surprised to find this video posted to Mastodon. I’m re-posting it here with Jim’s permission.

Not so twisted anymore

As I mentioned a couple of weeks ago, I’ve been contemplating ditching the twisted-pair feedline I have been using on my POTA doublet antenna, after having such good success with my friend Paul’s Cobra antenna. That antenna uses 450 Ξ© ladder line. I happened to have a 100-ft. roll of high-quality, 300 Ξ© twinlead, so I thought I’d give that a go. I’ve used this antenna twice now, and while it’s hard to prove conclusively that the antenna works better with with the 300 Ξ© feedline, it β€œfeels” as if it’s working better.

Of course, it could just be that band conditions have been better during my last two activations. That’s why I’d like to actually make some measurements. It’s not that easy, though. There are a couple of articles online that explain how to use an antenna analyzer to do this (1, 2), and I’ll give these a go once I’ve read and digested this material.

The downside to using 300 Ξ© twinlead is that it’s bulkier and less flexible than twisted-pair wire. It also seems more sensitive to environmental factors, such as touching the ground. But, taking a Β little care when setting up the antenna takes care of those issues.

QRN?? At the park?

It wasn’t all good news yesterday, though. There’s something at the park generating a hellacious noise on 20 meters. The noise is so bad that the band is practically unusable. This noise is somewhat noticeable on the other bands, but just barely, and certainly not enough to make the bands unusable.

That being the case, every one of the 40 contacts I made yesterday were on bands other than 20 meters. I started out on 40 meters, then jumped to 17 meters, which fortunately was open and active. I tried 15 meters, too, and made a few contacts there, but it wasn’t very active, so I moved back to 17 meters.

This noise is new. Last Thursday was the first time I’d noticed it.Β I would have made a recording of it, but I didn’t have an audio recorder handy on my phone. I will do next time I get to that part of the Pinckney Recreation Area.

On Mastodon, someone suggested that the noise was coming from a solar inverter. I hadn’t thought about that at the park, so I wasn’t really looking for solar panels, but I’m guessing that this is correct. Next time I’m there, I’m going to have to walk around and see if I see any. Β I might bring a small radio, too, to see if I can pinpoint the noise source.

Even if I do find the noise source, I’m not sure what I can do about it. I suppose that I can point this out to the park officials, but I’m not sure what, if anything, they’ll be motivated to do about it. Stay tuned for more on this. If you have any ideas of what I should look for, please let me know.

❌
❌