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Report on 2010 Pacificon Antenna Forum

2010/10/16 1 comment

It was difficult to climb out of bed at 3:45 AM to head down to Pleasant Hill for the 2010 Pacificon Antenna Forum on Friday, and I appreciate Steve, KJ6EIF, piloting us safely down and back.

I must admit that in my stupor at 4 AM, I was doubting this trip would be worthwhile, but now I’m so glad I went. The forum was a truly amazing, educational, and entertaining event.

Here’s a very quick summary…

  • Rich Holoch, KY6R, talked about his experiments with a variety of wire arrays for DX-ing, even when operated from from a fairly restrictive QTH. He showed many photos of his antenna configurations, including an interesting variation on a Bruce Array which performs quite well for him on 40 M and a modified W8JK beam for 20 M.
  • Dean Straw, N6BV – Gave a very detailed description of why the 2010 WRTC (“The Olymics of Ham Radio” held every four years) became an amazing event due to the sporadic E layer that formed near Moscow during the contest.  Team USA, R33M (N6MJ and KL6A) placed 3rd with 3,603 contacts during the 24 hour contest period. (BTW, that’s 2.5 contacts per minute on average.)
  • Steve Sterns, K6OIK, discussed the detailed science, math, and engineering related to SWR. This was the deepest analysis I’ve ever seen or read on the topic (serious electrical engineering level), and included a lot of insights regarding differences between SWR at your rig vs. the antenna, as well as many issues related to coax and mismatches.  I don’t think most of us understood every detail, but we have a copy of the notes if we want to dive deeper.
  • Jim Brown, K9YC, provided a entertaining and educational in-depth look of coaxial ferrite chokes. The conclusions where quite surprising and interesting, and I’ll be writing more about this subject in MendoRadio in the future. He provided the results of many of the tests that he’s done on different ferrite materials, and it’s not what you would expect!  BTW, one conclusion was that if you’re using a coax loop for your chokes, you need to reconsider that!
  • Edison Fong, WB6IQN, gave one of the most exciting and interesting lectures… I think we were all on the edge of our seats. As a warm up, he showed a 3 gig sampler board that they built recently that he thinks someday could be made for about $100!  This is essentially the receiver side of a SDR on steriods, and also makes a terrific low cost spectrum analyzer. The rest of his talk was the challenge to invent a new type of vertical antenna that was low cost, had no radials, all weather, with 5 db gain (over a standard 1/4 wave whip.)  Side note: It is non-trivial in the year 2010 to invent a new type of vertical antenna, but by-golly he did!  It’s a collinear J-pole stack — a wonderfully elegant and simple design. And he took all of the measurements to prove that it did in fact have the required gain.  This antenna is easy to construct, and I think we’re going to be seeing a lot more of them in the future.
  • Tom Schiller, N6BT – made a witty and funny presentation of UAD, unknown antenna disorder, that covered many of his adventures and misadventures of why antenna systems often fail.  Think you’ve got good barrel connectors on that lead-in? Well, think again!

Afterwards Steve and I checked out a few of the exhibits in the hall. Steve bought the dual band version of WB6IQN’s new antenna, and we drooled a bit on some of the portable QRP HF rigs being shown.  On the way back to the truck, we ran into a demo of hand-held satellite QSO using a dual band yagi with a gun grip for easy pointing.

All in all, it was a great forum this year. My only regret was I didn’t make plans to stick around for the weekend and see the other lectures and exhibits. Maybe next year! -Carl KB6ZST

Review of CW Decoders

2010/08/21 4 comments

I’ve been looking for good CW decoding software to use with my PC sound card for decoding CW on HF bands.

So far, I’ve tried these four programs. Two were poor, one was great, and the other was fairly good, but not the right one for me.

CwGet: I had high hopes for this decoder because it was popular on QRZ. It has several panels to display CW signals and includes various filters. Unfortunately, it does a very poor job of decoding the CW. Most of the output is junk.

CW Decoder: This one is similar to CwGet, but did marginally better decoding, which isn’t saying much. The biggest problem for me was that it has no option to set the font color, so on my system it displays black text on a black background! That alone made it unusable.

Fldigi: This is a great program. Far superior to the above, and with a good number of other digital modes. It’s got a clean, modern display and many special features. I’m going to write a more detailed review of this one when we start looking at digital radio modes and software.

CW Skimmer: This program is pretty cool. It can decode multiple CW streams at the same time, and it does a fairly good job of decoding them, but not perfect. It shows the CW transmissions in a horizontal waterfall so you can see what signals are around and allows you to judge their relative qualities. You can select the one you want, and change the bandpass to tighten in on it. Here’s a photo:

CW Skimmer
Multiple CW signals

You can check out more about it, including other photos, at http://www.dxatlas.com/CwSkimmer. For a while, I thought this program was free… but now it wants me to register, and the price is $75.00. To high for my needs. I suppose if you do serious CW contesting, you might find it worth the price.

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