Field Strength Meter

I’m going to use this new old stock Simpson panel meter for a field strength meter. I’m thinking of making it Arduino or Raspberry Pi based so it can be made wireless – have the sensing circuit out in the yard and it sends data and have the meter in the shack. Kind of a weird digital – analog mash up.

There are many circuits out there that are either analog or digital, so this could be a lot of fun.

The “Bouvet Bounce?”

A few months back, revised their prediction to show a “plateau” or “knee” in their Cycle 24 prediction, and the NOAA site just kept their previous prediction which shows how under performing this cycle has been.

Of course, this is like a Festivus Miracle, that right when you need the cycle to hold on just a little bit longer, it does.

If you look carefully at 2004 – 2006, you will see that there was this “last gasp” of upward activity before we hit bottom, so it is not that abnormal. The irony is that these DX-pedition planners just happened to hit the peak of Cycle 24 while on FT5ZM, and will probably get the best of this down part of the cycle for 3Y0Z.

This chrt doesn’t even have the big jump we have seen the past few days – where the SSN almost hit 100, which is quite amazing – but look what happened late 2005 – and then right at the turn of the year into 2006 – where conditions also swung really low.

Lets hope these big swings bring one last great big uptick when 3Y0Z is on the air.

There is still that QRZ.COM page for 3Y0I, but I remember the strange 3Y0G non event, so I still put my biggest hope on 3Y0Z.

After Bouvet, I will only need Glorioso to have them all. If they add Kosovo to the list (and I expect they will at some point), that will be a chip shot, so while I’d welcome a new entity, its no big deal as far as ATNO’s go.

I’ve gotten to the point where I believe Glorioso won’t be activated for quite some time – so I have to keep busy with other things – else I’d grow cob webs in my shack like I did during the last cycle bottom.

I’m betting on irony – that Glorioso will be activated at the bottom of Cycle 24 and that I will work my last QSO DXCC wise using a friends super contest station – in fact – I might do that and bring a bottle of champagne just because it would deserve that moment.

I do expect that I will work the last 13 on 160 before I work Glorioso, that seems to be the way its headed.

I’ll guess a year when I’m done with DXCC – 2020 – or 19 years after becoming a DX-er, and just a few years before I retire.


Autumn Equinox Conditions Predict Good 3Y0Z Conditions

About an hour before this screen shot was taken (2300z – ish) I was listening to local California hams on 40M SSB when all of a sudden the band went long – and it was like someone pulled a switch. Now – SO1WS is coming in S7. It was very cool indeed.

This is exactly how the autumnal equinox conditions start, and on cue – we are there. I’m going to bet that the morning LP to ZS will improve, but that night time short path to Africa will start improving. [UPDATE: ZS stations on the Long Path this morning – 9-4-2017 were quite good – not as good as usual, but the path is opening again]

I worked ZS8M in September, 2010, and here is what the solar cycle progression looks like between then and now:

I worked Pierre at 0409z on September 16th, 2010, and we were just barely coming out of a horrible several year bottom of cycle 23. I say horrible because I wasn’t a serious low bander – besides 40M, in fact, I had just missed 2 years that some say were the best on 160M. In 2010 I was still 3 years away from Honor Roll – so the higher bands had priority at KY6R.

What is most encouraging is that conditions (that haven’t felt all that great for some time now) are actually about what they were when I had my QSO with ZS8M. He had a very compromised antenna and 100 watts, and so – 3Y0Z in comparison will be at the other end of the spectrum.

So – this is pretty good news – and fingers crossed that we stay in the “bump” predicted by NOAA and others.

The “Mysterious” 30 Meters

This is my favorite book on radio propagation. Ian covers all bands and the theory is described in a way that is very easy to understand – and this is a fairly abstract and complex topic. ALL DX-ers need this book!

This is THE classic book on Lowband DX-ing. Get your copy because the ARRL is not going to come out with another version – this was John’s last edition. At least that’s what I was told by the ARRL. Its gets very technical, but it stands as one of the top books in my library – the learning experience has been outstanding.

What is very interesting is that the ON4UN book only covers 160 – 40M. This means that its pretty “hard core” low band. I know the feeling – if you are really worth your salt, you will work half way around the world on 160M. I worked FT5ZM and VK0EK on Top Band, and both are more than 11,000 miles away. There is only ONE entity that is farther away, and that’s FT/W – Crozet, and I do not expect to ever get a chance to work Crozet on 160M in my life time. As I understand it – Crozet will never see a mega DX-pedition, but will occasionally see an odd scientist visiting.

The joke amongst low banders is that 40M isn’t a low band – its more like 20M . . . (but I disagree and also feel that 30M is more of a low band than a high band) . . .

What really is interesting is how little information you can find on 30M. During the middle of winter during the years just before the last sunspot minimum, 30M was just awesome. Its “sweet spot” seemed to be in and around the TO4E – Europa DX-pedition in 2003:

I’ve drawn a box around the years where I remember 30M being awesome and a lot like 40M in the early morning in the Fall and Winter in the years 2003 – 2005. I remember that like 20M, 30M died and was closed at solar minimum. So it seems that that is why some say that 30M behaves like 20M some years.

I looked at my log and Clublog and cannot find a definitive pattern at all regarding 30M. I was thinking that 30M was best at the same time as 40M, and in a way it is – which is to say that 40M is by far the “best” DX-ing band if you want to work the world during all years of the sunspot cycle. I think 30M is not quite as good – because I do remember during the last bottom of the cycle that even 30M as dead when 40M offered some life.

I’ve always avoided 80M, but I need to start paying more attention. I earned DXCC on it and then stayed away.

I have been told about 2 years at the bottom of the last cycle when “160M was like 20M” – and boy am I ready for that.

This is why the most exciting times for me are at the bottom of this cycle – not in these “doldrums” where the numbers can be good or bad – but the disturbances have ruined things more than not.

However – I do notice that the aurora chasers have been very happy for what seems like years now.

Two Hybrids: 30M and the Mod Bob

The Mod Bob models best on 30M, and it matches the gain I get on my DX Engineering DV-40-P phased vertical array.

The pattern is very close to a Bobtail Curtain on 30M, but I think its more like an Extended Double Zepp if you just look at the horizontal part, and almost three elements phased almost like a Bobtail if you look at the verticals only.

What makes this so much fun is that the antenna is a “hybrid” just like the 30M band itself. From the ARRL Antenna Book:

10.1-10.15 MHz (30 m)

The 30-m band is unique because it shares characteristics of both daytime and nighttime bands. D-layer absorption is not a significant factor. Communication up to 3000 km (1900 mi) is typical during the daytime, and this extends halfway around the world via all-darkness paths. The band is generally open via F2 on a 24-hour basis, but during a solar minimum, the MUF on some DX paths may drop below 10 MHz at night. Under these conditions, 30 m adopts the characteristics of the daytime bands at 14 MHz and higher. The 30-m band shows the least variation in conditions over the 11-year solar cycle, thus making it generally useful for long-distance communication anytime.

I do remember how 30M can behave a lot like 40M at night and early morning, but I can’t say that I have ever seen it behave much like 20M. However, I haven’t really monitored it as much as I have 40 and 20M, so, with this antenna, maybe I will start checking into 30M more.

Final Notes on the U.RAT

I installed the URAT out back at the base of the “Mod Bob” antenna. I experimented for a few hours and I was able to get a decent SWR on 160, 80, 40 and 30 by doing this:

  1. 160M – bypass the capacitors and use a shunt coil at the antenna feed
  2. 80M – use the capacitors with that same shunt coil
  3. 40M – same as 80M
  4. 30M – same as 160M

There is one wire left in the control cable, this means with a clever use of a relay or two, you could bypass the capacitors for 160 and 30M. Here is a relay board that could be controlled with that last signal wire coming from the Raspberry Pi GPIO:

I’m pretty sure a simple DPDT relay does the trick – its NO or NC which means it will normally be set for 80 and 40M or 160 and 30M – and by using a button on the KPOD – or a simple switch in the control box – you could send that signal to the URAT relay and bingo!

This means for about 1/2 the price of the Palstar BT1500A, you can have an remote controlled balanced feed tuner. If you have the junk box parts – it would be less of course.

HOWEVER, I’m very spoiled by the Palstar BT1500A. It was $720 and worth every penny, by far. It’s design and high powered components give me the confidence that my antenna is coupled to my solid state amplifier, which is less forgiving SWR wise than the tube amplifiers, and every detail as far as matching the Mod Bob fits like a glove.

This has been the most interesting ham radio project I have ever worked on. I have learned so much – its really quite amazing. The project was rich in facets – antenna, matching circuits, Raspberry Pi, stepper motor control, a fun use of the Elecraft KPOD, and much more.

Its way too hot to go out and replace the URAT and put the BT1500A back out – so I will do it first thing in the morning.

U.RAT Version 2.0 and Experiments

The u.RAT that I will set up tomorrow will replace the Palstar BT1500A, but only as a test – to see if two Palstar C600 variable capacitors plus one inductor will work on 160M. I expect it will work on 160 and 30M, but not sure about 80M.

I split the control box and the drivers so that the Raspberry Pi Zero is in the control box:

Which realizes my original design, and it takes 7 wires in the rotator control cable, which is great:

The back has all of the connections that add power and signal out to the remote URAT:

And the on light and 12v to 5v converter is inside:

I have just the wires to and from the capacitors to wire up, then it’s a big finger crossing time early tomorrow morning before it gets too hot. I’ll need to experiment a bit using my fabulous Rig Expert AA-30, which I have gotten my money’s worth 100 times over.

If I need a coil or two, I’m hoping to wind them using refrigerator tubing and making them fixed. Here are some experiments I can try:

  1. Test with just the two variable C600 capacitors – they are rated at – 5.5 kV and 23-550 pF
  2. Add a shunt inductor at the input of the two capacitors and then at the output
  3. Add a shunt capacitor at the input and output of the two capacitors
  4. Add series inductors at the input and then output of the capacitors
  5. Some combination of 2 +3

If I do pull this off with these two variable capacitors and a coil or two – then I guess I wouldn’t have needed the Palstar BT-1500A, but since all of this was funded by selling my car – its all good. But if it does work – then the BT1500A either goes on the shelf or goes up for sale. Not sure – I really, really love this tuner.

SO – I have (and am still) learning so much – how much is that worth?