Duh: Learning Curve #2
September 1st, 2010 by kmack

Sunday I got the itch to get online. That means backyard portable when you live in an antenna restricted condo. So I put a card table up in the back porch and my 20 ft Jackite and 20m End Fed Half Wave in between the buildings.

Doggone noise and weak band conditions ruined the day so I decided to experiment with the new C Pole antenna that  Neil W0VLZ had suggested. To get rid of a hunk of fiberglass gel inside the barrel of one of the Black Widow Crappie poles I used my cheapo Harbor Freight rotary tool which is a lame imitation of a Dremel tool but gets the job done. A few minutes of fitting and I was good to go.

I’m pretty impressed with it though conditions did not allow for any QSO’s yet. I cut the wire a bit longer than Niel’s directions but it tuned up 1:1 at 13.889 on my MFJ 207 Analyzer. At 14.060 it was a bit over 1.4:1 which is plenty usable. Next time out I’ll do a bit of trimming and be right on the money! Compared to the EFHW in a 20 ft L configuration, it did seem a bit noisier but with condx so difficult it would be hard to tell without some instrumentation.

LESSON: The C Pole is a pretty fine design. I need to work on the physical setup to improve the way the antenna hangs. The crappie poles I used were a bit too flimsy on the top section and leaned inward from the weight of the wire. A better tippy top support system is needed.

LESSON: Niel’s C Pole base design and specs worked very well.  Lacking an empty plastic coffee can, I used a quart diet soda bottle of the same dimension and it worked very well for the balun section. With winds of approximately 15 mph and gusts to 20+ the antenna was stable and I did not use the spikes for the outriggers that I had prepared. Great work Niel. The weight of the base makes it a good choice for backyard or campground use.

LESSON: The C Pole would be a fantastic portable antenna sans the earth side supports. Chuck Carpenter W5USJ has posted a picture of this configuration. Take a look. One point hanger  and spreaders at the top and bottom and simple stake to the ground for anchoring it and you are good to go. I will be testing this next time out by the lake. Winner!

LESSON: The off center fed dipole folded like this and deployed vertically is a good compact option for antenna restricted hams. I bit more work on the frame and support system may pay good dividends in stability and efficiency.

Hope to fly this new antenna in its tree configuration this weekend. I’ll update my results then.


Kelly K4UPG PB #173

2 Responses  
  • Mike Weir writes:
    September 1st, 20106:32 amat

    Good morning Kelly, Sounds like a very interesting antenna. Me also being a fellow antenna restricted ham I will be looking forward to your report as to how it did in the tree configuration.

  • kmack writes:
    September 1st, 20107:53 amat

    Hi Mike! Thank you for the comment and stopping by the blog. I think this one will do well and if the weather and bands cooperate, I’ll give it a good test this weekend. Hope to work you on the bands soon.

    Kelly K4UPG PB #173

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