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Author Topic: SMALL SUPERANTENNA SUPERSLIDER COIL  (Read 6442 times)
K7FF
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Posts: 156




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« on: November 01, 2016, 05:51:27 PM »

I really like the W6MMA Superantenna MP-1.

In spite of the poor press by K0BG, I have a new mobile/portable HF project going and could really use two or three SuperSlider coil assemblies.

If anybody has a lead on any, please email info.

If I can get the stuff I need for the project, I plan to post the design info.

k7ff at att dot net
« Last Edit: November 07, 2016, 10:06:52 PM by K7FF » Logged
K0BG
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« Reply #1 on: November 02, 2016, 04:37:17 AM »

Without getting into a match of wits, there are much better choices than the one you cite.
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K7FF
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« Reply #2 on: November 02, 2016, 06:49:02 AM »

.
« Last Edit: November 02, 2016, 11:40:43 PM by K7FF » Logged
K0BG
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« Reply #3 on: November 02, 2016, 09:06:09 AM »

Well, this IS the mobile forum, but I suspect you could use a mobile antenna for another use and/or position?

The issue is the PVC used. While PVC is okay for some antenna parts, wherever there is high voltage—loading coil in this case—the losses get rather excessive, whether or not it is used as part of a mobile antenna. White PVC ages poorly in sunny climes, causing it to crack which adds to the loss factor. This said, if you're trying to get by on a shoestring, there are still better ways to accomplish an adjustable coil, regardless of its final use.
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K7FF
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« Reply #4 on: November 02, 2016, 01:22:42 PM »

.
« Last Edit: November 02, 2016, 11:41:42 PM by K7FF » Logged
K0BG
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« Reply #5 on: November 02, 2016, 01:46:46 PM »

I thought I made that clear. The major issue is the PVC they're made out of.

The dielectric strength of PVC (when new) appears to be as good as Delrin, and for the most part it is. But after it ages due to UV radiation for a few weeks, it literally tanks! And, PVC's loss tangent at 1 MHz is not nearly as good as Nylon or Delrin. It really gets poor in comparison at 10 MHz, and at 50 MHz, most PVC's become conductors. And this says nothing about its physical strength. The bottom line is, there are better choices for coil forms. The only advantage it has, is low cost.

You can research this for yourself, as all sorts of plastic properties are available on line.
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K7FF
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« Reply #6 on: November 02, 2016, 02:20:53 PM »

.
« Last Edit: November 02, 2016, 11:42:15 PM by K7FF » Logged
K5LXP
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« Reply #7 on: November 02, 2016, 08:20:52 PM »

Even NASA uses the SuperAntenna, PVC and all.  Check out the Netflix movie,

It's the perfect antenna to be in a science fiction movie.  Just like the full duplex Heathkit in the movie, "Frequency".

Mark K5LXP
Albuquerque, NM
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K7FF
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« Reply #8 on: November 02, 2016, 10:16:13 PM »

.
« Last Edit: November 02, 2016, 11:42:45 PM by K7FF » Logged
KK4YDR
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« Reply #9 on: November 05, 2016, 08:52:46 PM »

Whys all the post empty (edited out)? Just curious.
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K0BG
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« Reply #10 on: November 07, 2016, 04:35:17 AM »

Embarrassment.
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K7FF
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Posts: 156




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« Reply #11 on: November 07, 2016, 11:35:50 AM »

Embarrassment.
Are any of the thousands of posts made by K0BG not negative?  
« Last Edit: November 07, 2016, 01:14:29 PM by K7FF » Logged
K7FF
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Posts: 156




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« Reply #12 on: November 07, 2016, 11:42:38 AM »

Whys all the post empty (edited out)? Just curious.

KK4YDR:

I remove particular posts I make when they are no longer relevant to the discussion, or when responses are non sequitor.

« Last Edit: November 07, 2016, 11:49:16 AM by K7FF » Logged
SOFAR
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« Reply #13 on: November 07, 2016, 12:50:34 PM »

Embarrassment.
Are any of the thousands of posts made by K0BG positive. 

I have more respect for someone that lets their words stand.

Your post deletion is akin to the antics of a teenage female.
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K7FF
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Posts: 156




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« Reply #14 on: November 07, 2016, 01:10:38 PM »

Embarrassment.
Are any of the thousands of posts made by K0BG positive.  

I have more respect for someone that lets their words stand.

Your post deletion is akin to the antics of a teenage female.

Of course,
You are certainly right,
'Tis always better to stand your ground,
Never back down,
Than ever admit, that you're the clown.
« Last Edit: November 07, 2016, 10:15:17 PM by K7FF » Logged
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