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References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*\[TowerTalk\]\s+\[Bulk\]\s+Change\s+in\s+Frequency\s+As\s+Antenna\s+Height\s+Rises\s*$/: 6 ]

Total 6 documents matching your query.

1. Re: [TowerTalk] [Bulk] Change in Frequency As Antenna Height Rises (score: 1)
Author: Grant Saviers <grants2@pacbell.net>
Date: Mon, 30 May 2016 10:45:05 -0700
Ok, another cut at this with a much more complex model - 6 element 17m beam on a 48' boom. (I happen to have that model in EZNEC Pro4 and AutoEZ). Finding "resonance" isn't of much interest. What is
/archives//html/Towertalk/2016-05/msg00593.html (12,270 bytes)

2. Re: [TowerTalk] [Bulk] Change in Frequency As Antenna Height Rises (score: 1)
Author: "StellarCAT" <rxdesign@ssvecnet.com>
Date: Mon, 30 May 2016 14:10:31 -0400
agreed - but I have modeled my 6 element 15 and 5 element 20's. They are conversions using a 15M6-125 to create a high strength 15M6DX (as it models much better, especially in a stack) which I call 1
/archives//html/Towertalk/2016-05/msg00595.html (13,450 bytes)

3. Re: [TowerTalk] [Bulk] Change in Frequency As Antenna Height Rises (score: 1)
Author: Jim Brown <jim@audiosystemsgroup.com>
Date: Mon, 30 May 2016 15:42:28 -0700
On Mon,5/30/2016 10:45 AM, Grant Saviers wrote: My modeling (as G3TXQ comments) shows that max gain, min swr, and max f/b all happen at different frequencies. So, "tuning" a beam with swr seems like
/archives//html/Towertalk/2016-05/msg00600.html (9,548 bytes)

4. Re: [TowerTalk] [Bulk] Change in Frequency As Antenna Height Rises (score: 1)
Author: Grant Saviers <grants2@pacbell.net>
Date: Mon, 30 May 2016 19:53:15 -0700
Re the element to boom plates/clamps. I've found they make a noticeable difference with NEC4. However, they are hard to model since the Lawson substitute element diameters are so short to cause NEC 2
/archives//html/Towertalk/2016-05/msg00603.html (16,032 bytes)

5. Re: [TowerTalk] [Bulk] Change in Frequency As Antenna Height Rises (score: 1)
Author: "john@kk9a.com" <john@kk9a.com>
Date: Tue, 31 May 2016 07:04:29 -0400
Yes, insulated elements are much easier and more accurate to model. I also try to avoid having very short segments in my NEC2 model. Insulated elements also make it easy to model the boom for interac
/archives//html/Towertalk/2016-05/msg00610.html (7,539 bytes)

6. Re: [TowerTalk] [Bulk] Change in Frequency As Antenna Height Rises (score: 1)
Author: "StellarCAT" <rxdesign@ssvecnet.com>
Date: Tue, 31 May 2016 07:35:17 -0400
Thanks Grant, I worked with Greg, '8WWV, for quite a bit of the modeling - he would run my models using NEC4 ... and although he'd get a slight shift in frequency his results were similar to mine tha
/archives//html/Towertalk/2016-05/msg00612.html (12,404 bytes)


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