Post by ac6la on Mar 11, 2011 22:30:41 GMT -5
The Zplots Excel utility now has the ability to calculate and plot various attributes of transmission lines such as characteristic impedance, velocity factor, and loss. Basically you attach one end of the line in question to your AIM or VNA device, terminate the other end with an open circuit, run a sweep over a frequency range of interest, and save the data file. Terminate the line with a short circuit, run another sweep, and save the data again. Then use these two data files along with the physical length of the line as input to the new Zplots feature.
A complete description of Zplots and a download link may be found at:
www.ac6la.com/zplots.html
Please see the "Change History" section near the bottom of the page for an overview of everything that is new with this release. If you'd like to just find out more about the transmission line measuring feature see:
www.ac6la.com/zplots.html#MeasureTL
There are also two appendices that may be of interest, one concerning "Antenna Measurements via a Feedline" at:
www.ac6la.com/zpapndx1.html
which addresses a topic that comes up on the forums from time to time and another about "Seeing the Effects of Phasing Lines" at:
www.ac6la.com/zpapndx2.html
which contains a fairly detailed analysis of different feed methods for a simple two-element phased array.
A related Excel workbook named Feed2EL.xls is described at:
www.ac6la.com/feed2el.html
Note that Zplots requires Excel 97 or later. It does *not* work with other spreadsheet software such as Open Office Calc, Quattro Pro, or Microsoft Works. None of these other spreadsheet programs fully support the macros used by Zplots.
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New release of TLDetails available
TLDetails is a stand-alone utility (does not require Excel) also related to transmission lines although you cannot use it to determine line attributes based on actual measurements as with Zplots. TLDetails has a built-in library of approximately 100 different line types and has been modified to use the same mathematical model that is used in Zplots. This new release also has a few extra plotting functions. Full details including change history and a download link at:
www.ac6la.com/tldetails.html
Dan
AC6LA
A complete description of Zplots and a download link may be found at:
www.ac6la.com/zplots.html
Please see the "Change History" section near the bottom of the page for an overview of everything that is new with this release. If you'd like to just find out more about the transmission line measuring feature see:
www.ac6la.com/zplots.html#MeasureTL
There are also two appendices that may be of interest, one concerning "Antenna Measurements via a Feedline" at:
www.ac6la.com/zpapndx1.html
which addresses a topic that comes up on the forums from time to time and another about "Seeing the Effects of Phasing Lines" at:
www.ac6la.com/zpapndx2.html
which contains a fairly detailed analysis of different feed methods for a simple two-element phased array.
A related Excel workbook named Feed2EL.xls is described at:
www.ac6la.com/feed2el.html
Note that Zplots requires Excel 97 or later. It does *not* work with other spreadsheet software such as Open Office Calc, Quattro Pro, or Microsoft Works. None of these other spreadsheet programs fully support the macros used by Zplots.
=============================================
New release of TLDetails available
TLDetails is a stand-alone utility (does not require Excel) also related to transmission lines although you cannot use it to determine line attributes based on actual measurements as with Zplots. TLDetails has a built-in library of approximately 100 different line types and has been modified to use the same mathematical model that is used in Zplots. This new release also has a few extra plotting functions. Full details including change history and a download link at:
www.ac6la.com/tldetails.html
Dan
AC6LA