Posted on September 1, 2017
I stumbled on a suggestion for a balanced tuner circuit that is suggested in an old Collins 32-V3 transmitter manual. The top circuit is one that I am most interested in. I’d love to try it and compare it to the Palstar BT1500A – which works perfectly, but it would be super if I could use the URAT with two variable capacitors and a fixed tapped inductor.
This “series tuning” circuit I just have to try.
Posted on August 30, 2017
I worked on the TX5K Clipperton DX-pedition a few years back, and it was the “warm up” for working on the VK0EK Heard Island DX-pedition. TX5K did receive a very nice award – the “Best Communication” award for our work in communicating “near real time” with DX-ers, Sponsors and Dx-peditioner family members during the DX-pedition. But if you go to the GDXF “Mega DX-pedition Honor Roll” page:
You will see that TX5K – which was mainly the Bavarian Contest Clubs doing, deserves an award in this class. Its nice to see them mentioned and listed on this site – because its quite the accomplishment!
VK0EK also just won this award as well. VK0EK also went on to win the DX-pedition of the Year Award:
There are many different ways to slice and dice the statistics, and like my friends – who are really into baseball and especially pitcher stats – its fun to see why they like one pitcher over another. The same thing can be done with DX-peditions, but for me – it was just a joy and a lifelong great memory to have been very involved with VK0EK and involved with TX5K in a meaningful way.
Hats off to the teams who activated these entities, and to all DX-peditions and DX-peditioners – its a lot of work and a huge commitment in time and money.
Posted on August 30, 2017
I’m going to add the URAT to a 70′ tall wire vertical with 96 buried radials, and this is a classic 80M quarter wavelength vertical. Its an unbalanced feed with an unbalanced antenna. It will require an L matching circuit:
I like VE7BPO’s diagram, and I am guessing that I will need to wire the variable capacitor and roller inductor using circuit B, but I will report back this weekend.
This is the BT1500A circuit, which is a balanced tuner where you can switch the capacitor to be at the input or output of the dual roller inductors. This is perfect for the “Mod Bob” antenna, and is quite different than a simple vertical feed.
Its funny, but I’m becoming exclusively a low band only DXer, and I do believe this is where I will stay. The low band antennas will still let me work the higher bands, but not as well as with a high yagi. In fact, I will take down my 2 element 20M home brewed yagi after I make Top of the Honor Roll, and that will be it for the high bands. I also am not interested in climbing roofs or towers any more, and am happy that I don’t have anything big and heavy hanging over my roof. If anything happens to my low band antennas, they are very easy to maintain and require no climbing.
Posted on August 30, 2017
Simple LC circuit for matching a vertical
I’m going to put up a 70′ vertical wire into a tree and feed it against 96 buried radials. This can be done alongside the Mod Bob, and I can use the URAT to remotely tune it.
This will be my Labor Day Weekend project just because its fun. It will be dedicated to 80M. It might tune fine on 30M since its close to the 3rd harmonic.
This should be fun while I watch the DX Grass Grow.
Posted on August 28, 2017
Its pretty funny, a couple mornings ago it was so cool I had to wear a jacket in the shack. We almost hit 49 degrees F. I had blogged how August has been a cooler than normal month – albeit just because of a thick and persistent fog along the coast that is more normal for June than August. Yesterday it hit 107 degrees F here – so I must have jinxed it.
This morning I heard the strongest signals on 160M coming from VK, ZL and Alaska – much stronger than I have heard in many months. We also just had a great 40M opening to ZS on the Long Path, so maybe the equinox will kick us back into low band DX “season”.
Of course, I need 13 new entities, and while it should be easy – the trick is variety – that more entities have hams on Top Band on those entities or that more DX-peditions take 160M more seriously.
If I were on the East Coast it would have been a wrap a long time ago – only 6M would be harder to achieve DXCC from the West Coast.
Fingers crossed for Top Band.
Posted on August 27, 2017
There were three announced 160M activations this summer that never happened.
There have been at least 4 mega DXpeditions whose 160M activation was pitiful in the last several years. I do understand that its a hard band to put antennas up (and keep them up) and that it also doesn’t have the “ROI” that other bands offer.
I had expected as we slide down the sunspot cycle that more would be interested in Top Band. But it seems like just the opposite is happening.
I’m wondering if Top Band has seen it’s best days or if I’m just a little ahead of myself. Autumn is almost here in the Northern Hemisphere, so fingers crossed that there will be more 160M DX.
Posted on August 26, 2017
I’m very pleasantly surprised that my latest big excitement in Ham Radio and “Making” is reading about the physics of electronics. Its because I am finding this book to be fascinating.
When I was at University of Pennsylvania at Lock Haven in the late 70’s, the physics professor needed a full class for an electronics class he wanted to teach. Lock Haven did not have an engineering curriculum that I knew of (besides Computer Science and which is the program I was enrolled in), but what stood out is that the professor advertised that the course was offered for those who were pursuing a physics / science degree and those who were not. He basically split the class in what I called Electronics for Smarties and Dummies. We shared the same text book, but us dummies took a much simpler test each time we had a quiz or test. The smarties had to do calculus, us dummies, trigonometry (at best). I remember being totally amazed reading about semiconductor physics especially. How in the world did anyone conjure up such notions?
Answer: The Diode. Take the physics surrounding a Diode, and then build on that. NOW – the Diode in radio started out as the “coherer” – which is where receivers started. A little history and physics combined is just too cool, and its the kind of thing I think of on BART or on my bike rides.
What I love about this book is that it reminds me of that Lock Haven class. The authors start with a really superb description of the physics with great diagrams, then they show the simplified trig equations, and then the full on calculus. I like it because while the calculus loses me – I like to see how the theory is more involved than what I have learned in the ARRL Handbook, the ham tests and whatnot.
I’m going to decommission the URAT tomorrow an re-use its parts for future projects. I simply don’t need it because DX-ing has become mind-numbingly boring – like watching the grass grow. Heck – having to go out with my Rig Experts AA-30 and a coax cable to manually tune the remote tuner gives me something to do in between what seems like months where I actually work anything I need.
What really excites me is reading about Thevenin’s Theorem or whatever and then building a little circuit and using my test equipment to see whats going on. I also have various Arduino shields and Raspberry Pi hats that I want to play with, and code I want to try.
This is all just for the fun and education – andvfor no other reason. I am finding that just being inquisitive and learning has been leading me down paths I normally wouldn’t go down, and its kept me in the shack doing something, and having big fun.
I also love the fact that I can share knowledge and have some fun techie stories to tell. I have several people visiting the shack for Maker stuff, but they then look at the Ham gear and get interested.
Giving presentations is also a blast, and I’m really excited about Pacificon – more than ever because I have one Ham low band antenna presentation and one Maker URAT presentation.
I found out that the Pacificon seminar schedule will be published on September 1.
When I wrote yesterdays blog post – and where I have been “colluding” with Mike, KJ4Z on techno-philosophical things related to DX, I find that my mind expands and some very cool “unintended consequences” of the good kind happen.
Learning is Rad.