80M Phased Array: DX Engineering DV-80-P

I like my DX Engineering DV-40-P so much that I will most likely put up an 80M phased array as soon as we get to the bottom of this cycle – which I believe will start toward the end of this year. I would have 3 dB end fire and 1 dB broadside, which would make me competitive on 80M and 40M (with the DV-40-P and UrbanBeam) for 3Y0I.

As much as I love Top Band, its just not productive on the West Coast. Because Bouvet and Glorioso will most likely be activated during the dearth of this solar cycle, 80M would be a much more likely band to work them on than 160M, so after a couple more Q’s on 160M, I might change horses.

I can easily and inexpensively add a wire in a fiberglass pole on top of each Spiderbeam 41′ mast. A cheap MFJ 33′ light duty pole is only 3 pounds, and with a well guyed Spiderbeam push up mast, that would easily handle the top load – much better than trying to tack on aluminum.

Speaking of 80M, I’m listening to a JA who is very strong right now – and there is nothing on 160M. I think 80M will become a real band in my “quiver” this cycle bottom.

My New “DXCC”

I’ve lost 4 pounds in the last 4 weeks. Its watching the carbs and exercise. The biggest surprise is how much I love weight lifting all of a sudden. With DXCC, the goal was to make the count go up, with weight loss, the count goes down. I ride my bike to and from BART to work in SF, I lift weights and do yoga.

I’m a goal oriented person, and while retiring from DXCC left me feeling a bit “stateless”, this new healthy program has me in a similar mindset as when I was chasing DXCC. Once you get in your 50’s, you need to boost your metabolism – and I had read that weight lifting is a great way to stoke the metabolism fires. I sure can validate that!

80M Phased Array

80M Phased Vertical Array using 2 Inverted L’s

I’m playing with what an 80M phased array would look like, with shortened elements.

The first attempt at modeling this in EZNec shows that there is end fire and broadside gain (“almost” 3dB end fire 1 dB broadside), but the pattern isn’t as good as having 60′ verticals.

A while back I had a 60’vertical that used the Spiderbeam 41′ push-up mast, and then “softer” aluminum above that for another 19′. It was too top heavy, so I might look into adding 20′ with wire inside the lightest fiberglass push up mast.

I’m only designing this now, but as I said in yesterday’s post, 160M from the West Coast means you can turn on the radio and sometimes not work any new ones for months.

That one night when 80M was super open, 160M was anemic at best.

Anyway, just more fun ideas in antennalandia!

A Weird Thing Happened on the Way to 160M DXCC: 80M!

160M is agonizing from the West Coast – its really hard to make DXCC here. I can’t even imagine 6M – that would be far worse. HOWEVER, lately I have seen 80M open up like 40M does, and it offers so much more DX than 160M does.

I have no idea why, but I have always hated 80M. No – its not because of 75M – hi hi. There is no good rational reason, and now that we are dropping into the sunspot abyss, I am seriously thinking about taking my spare Spiderbeam aluminum push up masts and turning them into a phased array on 80M.

I have the buried radials (96), the real estate (barely), and the verticals. Hmmmmmmmm…….

Maybe when we hit the bottom of the cycle and when “80 is like 20M”!

ALM-31 Details

US Towers ALM-31 – Photo Courtesy of Andy, AF3I

On the base of the ALM-31 is a “clevis” joint, which lets you walk the mast up. I will build a simple base for my very sturdy and reinforced deck.

US Towers ALM-31 – Photo courtesy of Andy, AF3I

Andy does not use the welded on rotator bracket, so he has it turned upside down. In my case, I will mount a Yaesu G-450 on it, and a very small pipe above that for the SteppIR UrbanBeam.

The UrbanBeam arrived today and I will start its assembly this weekend. The ALM-31 will follow, so I am in no big hurry as I expect it could be  while before I get the tower.

Anyway, my next fun project kicks off my “Post DXCC” chapter of DX-ing for me.

US Towers ALM-31

Image Copyright US Towers

US Towers has a nice crank up aluminum tower / mast that would be perfect for the UrbanBeam. I also saw these up close at Dayton last May, and like the UrbanBeam – it caught my eye. At the time I was still fully focused on DXCC, so these products were put in the back of my mind.

Image Copyright US Towers

The strength and weight makes this perfect for my new “Post DXCC” situation. These two products that I saw at Dayton popped back in my mind as soon as I hit 9BDXCC and along with the cancellation of 3Y0Z.

One operating idea that I have also had – but which was also stashed in the back of my mind is the USA County Hunters Award. It would be perfect for the bottom of the Sunspot Cycle and also get me into serious “Retirement Hunting” as far as where we might retire to. Our first choice is Bend, OR, but I want to really consider as many places as I can. One example: a year ago we visited our relatives in Eugene and we stopped in Corvallis and Cottage Grove. We learned that Lane County has the most covered bridges West of the Mississippi. Having gone to college in PA, that was especially cool. We also rode our bikes past the Hop fields between Salem and Corvallis, which was another highlight. Chasing County Hunters would unfold quite a few interesting tidbits and stories.

I have no idea when I will retire, and expect to be in Orinda at least 5 more years. The nice thing about the UrbanBeam and this crank up mast is that I can take them with me when I retire – that’s why I do not want anything big and heavy. No big antennas or towers or amplifiers.

Its a good feeling to be looking at my next “chapter” – its just starting to barely form now.

40M LP and SP Take Off Angles

The F1 layer exists only in summer, and during the Northern Hemisphere Winter, our F2 layer means that we get more distance covered by each hop. At ZS they have both F1 and F2 because its their Summer.

ZS6CCY has a low take off, high gain antenna – 3 element yagi up high on 40M. This is why he always will be doing most of the work. Here is the Short Path:

My lower take off phased array works best after our sunset. I’m going to guess that my first hops – that would go over the US, would benefit if they did not bounce off land – so the lower angle prevents this. ZS6CCY has gain, low takeoff angle and salt water on both SP and LP for the first hops.

During the morning sunrise at my QTH, my rotatable dipole, with a higher take off angle does best – and I can only imagine it has more to do with me bouncing off water – and maybe its also because the F layer is rising. I’m still not sure why a higher take off angle is better . . .

Here’s another variable. My terrain. During the nightly SP – my east direction has an immediate hill that I have to try to go over. Why my lower take off angle antenna is best is a mystery. For the morning long path – I have a lower hill to get over.

  • Terrain seems to not matter
  • The charging of the ionosphere and the F1 and F2 composition seems to be one part of this puzzle
  • The fact that I am bouncing off salt water means whichever antenna supports more water and less land seems to be a second part of the puzzle

The wild card would be some kind of chordal hopping or ducting is happening during my morning sunrise. The higher angle would get the signal in the duct where the ionosphere is charging and rising, and it requires a higher angle to do so. If you look at the Long Path – both stations have sunlight. On the SP – both are in dark. This has to be a key variable. If I had to give my answer – I’d say chordal hop or ducting happens when both stations are in sunlight.

On page 49 of the Ian Poole (G3YWX) book “Radio Propagation – Principles and Practice”, this situation does seem to be a very strong possibility. He even shows a diagram where indeed – a higher angle would be helpful, and a low angle at ZS6CCY’s QTH would not matter.