Today involved some experimentation as well as a POTA activation. I tested some changes to the radials I use on my hamstick system out of curiosity and came away with some interesting results. Read on to see the AAR and the results of this test.
Today was supposed to be a quick little activation and then I was going to do a few other things, but plans are made to be changed from what I can tell as the bands were doing well for me and I stayed longer than I planned. But then the sun can bring that full circle as you will see below.
The operating position today shown above, was on top of the hill at the frisbee golf course and on the bed cover of the truck. Turns out that was somewhat of a bad idea. It just got hotter as the day progressed and the sun quickly came over the door I was using to shade me. This is what ultimately caused me to go QRT when I did as I was having a decent run on 20 meters at the time. It was just plain hot, with the sun seemingly cooking my right ear while I was working ops. I did enjoy working several ops today I have seen in my log before plus some that I have not. I even got a Canadian which is always nice.
This is probably the best image of my 40m hamstick and mount I have ever gotten. With the sun in the right spot, the whole antenna lit up well enough for the camera to get it. The setup is not actually mobile as it requires a counter poise to get it to work it’s best, but wow… it worked really well today, especially well today actually for some reason. I can hear surprisingly well on these tiny HF antennas too. I own three different brands of hamsticks (covering 40, 30, 20, 17 and 15) and can not tell a difference in any of them as far as how well they work. They all just work really well.
These two photos tell a story about what was happening at the location today on 30 meters. When people talk about having RF noise at a location, this is what it looks like on a radio that doesn’t have a waterfall display. The photo above is what the noise floor looked like when the RF noise was not present and the bottom image is what it looked like when it started up. It also was not constant, but appeared to by cyclic in nature as it would spool up and would just be some sort of hash for about 20 seconds and then it would just go away for about 30 seconds maybe longer. I would be able to work one contact and then it would come back and if the hunters were not transmitting with an S9 signal, I couldn’t hear them. This is really frustrating and is one of the reasons I don’t activate 30 meters more than I do. But so it life and how much fun would it be if we never had problems to solve? It would get pretty boring pretty fast… Even with this RF hash coming in and out, I was still able to get 9 calls in the log on 30 meters today so I count that as a win anyway.
The next thing I want to share about today has to do with the antenna system I was using. I have made tuned radials for all of my hamstick except the 15 meter unit (I have not deployed it yet, but soon I will.) I went to a lot of trouble to tune these radials too, with a ton of time at home working on this. Well, it turns out that I didn’t need to do that for the 30 meter hamstick at all. I deployed my nanoVNA today and did some measurements on the hamsticks to confirm nothing has changed with them and figured out something just out of curiosity. Seems that the radials for 40 & 20 meters work just fine on 30 meters too. This means one set of radials for all three of those hamsticks. Next outing I will take the 17 and 15 meter hamsticks and tune them up and see if the same radials will work on them too…fingers crossed. I am always looking for ways to simplify my station setup and the radials has been one of the slowest things to deploy of all the gear for POTA with the hamsticks. So if I can get it down to just the two radials and not having to remember the color codes for them and such I will count that as another win in my book.
The above photo shows that the antenna is fine on the 20 meter CW section, even though it is technically low on the best part of the chart, it is only 1.188:1 where I normally work on the 20 meter band. Well, knowing that, below is what it looks like on 30 meters with the 40/20 meter radials instead of the tuned radials I made up for just for the 30 meter band. Pretty crazy huh? Looks almost identical to the 20 meter chart and even almost matches the 20 meter SWR value. I was blown away by how good this turned out and to think I have never even tried it before today… Another thing I noticed about hamsticks in general is that they act like bandpass filters across the HF spectrum, I did open up the range on the nanoVNA and it does have other nulls IN THE VHF SPACE, but each hamstick has ONLY ONE spot they are resonant at in the 0 - 30mhz spectrum. No multiple harmonics like the EFHW, just one really deep SWR null is all you get. So plan accordingly, but to be honest, it works really well so I am not going to complain. I think this might actually work as a band pass filter but have not had the chance to test it yet. Maybe I will set this up at winter field day and see what it sounds like there. That should do it.
Here is the log from this activation and the signal reports look good for a mismatched antenna on the trailer hitch of my truck. I was using 15 watts though so that might have helped some. I have been sending with more power lately to just play with the Argonaut to see how hot the heat sink gets at various power levels and on CW it barely gets warm at all with 15 watts of RF so I am really happy with that. I am doing this test since i changes the fan a while back to reduce the fan noise as the factory fan is quite loud. I have a blog post showing what I did with this if you are interested in that.
All in all I learned something new and had a great activation at the same time. So till next time go get your radio out and make some contacts on it!