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## Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals

 To: Discussion of Ten-Tec Equipment Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals Steve Hunt Discussion of Ten-Tec Equipment Fri, 27 Jan 2012 13:10:49 +0000 mailto:tentec@contesting.com>
 ```Hi Joel, Nice to hear from you! The ladderline loss figures quoted in the Antenna Book - which I believe are also repeated in TLW - are out by a factor 2. It's very easy to demonstrate that with a simple I^2R loss calculation. I'm happy to show the sums if you need convincing. Tenths of a dB differences may not matter of themselves. However, they *do* matter when the losses you are trying to measure are of the same order. In your article you said that the measurements on dry line agreed with TLW predictions "within a few tenths of a dB in each case". Given that the TLW loss figure for ladderline is 0.05dB at 3.7Mhz, measuring something "within a few tenths of a dB" of that figure could represent a *gross* difference. Also, we need to remember that in many (if not most) Ham applications ladderline is operating at a high VSWR, so what might seem to be negligible differences in *matched* loss figures become much more significant in real life applications. I think the most puzzling result you reported was the substantial increase in loss (3dB to 10dB) when you set the line on dry ground, whereas there was virtually no increase in loss when you set the line on wet ground. When (or is it if) our UK weather improves, I intend to try some measurements myself. 73, Steve G3TXQ On 27/01/2012 02:44, Joel Hallas wrote: > Steve, > > Well, I'm not sure if TLW is exactly on or not, but I'm pretty comfortable > with our technique. When we're talking differences of 0.1 dB, not sure if > the exact value is too critical for the usual HF amateur. > > Bob and I took careful data, rematched with every new set of data to > compensate for any Zo differences and used good, commercially calibrated > gear to take the data. > > Regards, Joel Hallas, W1ZR, BSEE, MSEE > Westport, CT > _______________________________________________ TenTec mailing list TenTec@contesting.com http://lists.contesting.com/mailman/listinfo/tentec ```
 Current Thread Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, (continued) Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Phil Sussman Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Rick - DJ0IP / NJ0IP Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Jim Brown Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Carl Moreschi Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Rick - DJ0IP / NJ0IP Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Joel Hallas Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt <= Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Joel Hallas Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Joel Hallas Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Joel Hallas Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Joel Hallas Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Steve Hunt Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Jim Brown Re: [TenTec] Re. [Ten Tec] Grounds and balanced fed verticals, Phil Sussman