Cloudwarmer Help - Grounding?

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by KG5NNA, Jun 16, 2017.

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  1. KG5NNA

    KG5NNA Ham Member QRZ Page

    Good day!

    I was recently given a reasonably new Alpha-Delta DX-B antenna. This is apparently a fairly mediocre multi-band antenna from 160 to 30m and supposedly is a sloper.

    I don't have access to put this thing at 35' and slope it, so as a kind of experiment, I'm going to attempt to install it as a cloud warmer on my fenceline abut 6' off the ground. The install should be straight forward, except I want to trim the parallel line (30m) a little to use it at 20m instead (I'll try this by just some tuning first).

    Question is that the install manual refers to a dedicated ground for the antenna running from the mounting bracket to the ground. I'll bite to put a ground rod near that end of the antenna. The ground wire from the bracket to the ground is likely to be around 6' of course. I'm trying to buy some ground wire for that short distance, so will 10-gauge insulated solid copper wire be ok for this experiment? I seem to remember that some hams prefer 6 or 8 ga, but that's more expensive and harder to obtain at Home Depot or Lowes. I can get a line of 10' of 10 gauge for a low price. I might even use it for my shack's RF ground also.

    The NEC document doesn't seem to mention the minimum gauge, so any help here from your personal perspective would be helpful.

    Many thanks and 73.
    Korky Kathman KG5NNA
     
  2. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    Try it, nothing to lose.

    My experience with the DX-B specifically (having used that model) is it works fairly well when installed on a conductive tower at least 35' above ground, and the other antennas on the tower such as beams rotating above the tower influence resonance and performance.

    If you install it with only a 6' long ground wire and have it installed horizontally at only 6' above ground, I suspect it will not be tuned at all and adjustments will be required -- possibly major adjustments. If it resonates "below the bands" (which I think it will) and you have to shorten the element lengths substantially, that might bring it into resonance but will also further narrow the operating bandwidth, which on 160m and 80m is really narrow to begin with, even when properly installed. You "might" end up with an antenna that only loads across 20-30 kHz without becoming terribly mismatched.

    However "any antenna is better than no antenna!" so I'd recommend you try it and let us know what happens.
     
  3. KG5NNA

    KG5NNA Ham Member QRZ Page

    Yep I agree. Here's the real scoop. It was given to me and over the next month or so, I intend to put up a Hustler 5BTV Vertical with lots of radials. However, my hunch is that will be great for DXing long distances but because of the angle I doubt I'll get anything reasonably local (say 500mi). The BTV is 5 bands so I look forward to DXing with that. The cloud warmer, I thought MIGHT get me something inside the 500mi that I'd lose with the BTV. I'm not expecting to use it for the 160-80m anyway, but more 20-40m if it will tune without too much consternation. The BTV covers 10, 15, 20, 40 and 75-80. So there's overlap there. I'm just theoretically thinking the take off angles won let me talk inside a 500mi radius.
     
  4. N8CMQ

    N8CMQ Ham Member QRZ Page

    I suspect your cloudwarmer will be a wormcooker instead.

    If you can`t get one end up in the air, it will not radiate much.

    As for local operation with the vertical, it will be fine for DX and local, as very little signal comes from directly overhead, otherwise, people would have yagis pointed straight up all the time...
     
  5. KG5NNA

    KG5NNA Ham Member QRZ Page

    I might add that I actually got this idea from an Elmer who had a small home and no way to get anything airborne. He had a similar A-D version, though not the DX-B and ran it along his fence and apparently was very pleased with the results. He has since moved out to a more remote location with more acreage. I'm in a one-story residence in a suburb so the extent of "high" for me is about 17'. That's too short for this antenna, plus I'm not gonna get on a ladder at my age either!. So, we'll give this a try, it's a little expensive for the experiment since I'm burning about 100' of RG213 as the feedline, but if it doesnit work well, I can always play with other solutions. Guess that's 1/2 the fun. My investment, however, will be the 5BTV.

    So I havent' heard anyone comment on the ground wire size? I can get 6 ga, but 10ga is cheaper and more readily available. There seems to be some question whether I even NEED a ground on the A-D at all!
     
  6. N5JWJ

    N5JWJ Ham Member QRZ Page

    a close read of the instructions will tell you that the metal pole or tower is the other half of the antenna. that is the way it is designed for the tower and top load of antennas to add capacitance and reflection. As others said try it, but do not expect much out of it
     
  7. KG5NNA

    KG5NNA Ham Member QRZ Page

    May never need it if my vertical will have a decent range. It's a nice weekend project and the worst case is that I get a bunch of nothing. Which is what I have now! And the BTV will end up being my main HF antenna anyway. Thank you all for your comments and insight!

    73
     
  8. KA9UCN

    KA9UCN Ham Member QRZ Page

    I suspect you will have a dud above NVIS frequencies and a functional NVIS antenna below critical frequency. I would run a ground rod on the end and attached wire the length of the antenna along the bottom of the fence. At one tine I used a resonant 80 meter loop at 15 foot above ground for QRP 80 meter. I had a respectable signal in the 100 to 250 mile range.
    It might also prove out to be a good receive only antenna.

    Joe KA9UCN
     
    NH7RO likes this.
  9. K4SAV

    K4SAV Ham Member QRZ Page

    The ground wire can be most anything.. #16 should be easy to get.

    I suspect that your 5BTV will beat it for NVIS, even though the 5BTV has a null overhead. Gain is going to be really low on the low bands. If you are going to use it only on 20 thru 40 meters there isn't going to be any NVIS propagation anyway. 500 miles isn't NVIS on 40 and 20.

    Jerry, K4SAV
     
    Last edited: Jun 16, 2017
  10. KG5NNA

    KG5NNA Ham Member QRZ Page

    Gotten great feedback from BTV owners...only thing is to have lots of radials. Again, I'm not really looking to score at 160m. Not even 80 for that matter. 10-40 is what I'm hoping to enjoy. Would like to get to DX a but and go digital.

    Joe thanks for the tip. I can grab some 14 or 16 ga at Lowes for that fence runner. I have a guy coming tomorrow to drive the ground rods (2 near my shack for RF and the one for the other antenna. Hopefully by the weekend I'll have something to test.
     

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