Antenna Tuners: The Math (076e)

In my video on the Feedline Side of the antenna tuner, I refered to a mathematical exercise that I performed using a spreadsheet. I had some requests for a video showing the math that I used. That is what this video is all about.

Do not worry, the math is very simple and easily done on your scientific calculator. I will step you through it all, one step at a time.

In this video, I will present three methods for determining the total loss of power delivered to the antenna given that you know the SWR at the antenna and the loss of the feedline (Matched Loss).

If all you know is the SWR as measured at the tuner end of the feedline, I will show you how to calculate the SWR at the antenna. I will also show you how to calculate the power actually being delivered to the antenna.

The first method uses the chart or graph presented in the American Radio Relay League's Antenna Book or in Walter Maxwell's book, "Relfections." This is the "Graphical Method."

The second method uses the math from my 1984 copy of the A.R.R.L. Antenna Book.

The third method is the Spreadsheet Method. It is the method that I used in my video on the feedline side of the tuner. It will give us an inside view of the entire process and help us to see the equilibrium being achieved. You put in the SWR at the antenna, the power provided from the transmitter and the native loss of the feedline (matched loss). It, then, does the rest for you.

Here is the LINK to the ZIP file which contains the Excel Spreadsheet.
https://drive.google.com/file/d/1KOcc...
While the sheet is locked, there is no password.
I locked it to prevent accidental changes.

Here is a LINK to the formula sheet to go along with the video:
https://drive.google.com/file/d/1D5q4...

I reference the following very helpful book:
"Reflections III: Transmission Lines and Antennas"
By: M. Walter Maxwell, W2DU
Published by: CQ Communications (c) 2010

======= VIDEO LINKS ==========
Antenna Tuners: Impedance and SWR (076a)
   • Antenna Tuners: Impedance and Feedline SWR...  
Antenna Tuners: The Feedline Side = The Source and Destination of Reflected Power (076b)
   • Antenna Tuners: The Feedline Side = The So...  
Reflected Power: Lost then Found (076c)
   • Reflected Power: Lost then Found (076c)  
=======================================
Time Markers for Your Convenience
----------------------------
00:05 Introductory Comments
01:35 What You Need to Know
04:51 Method #1: The Graphical Method
08:28 Method #2: The Mathematical Method
11:01 Method #3: The Spreadsheet Method
14:53 Final Comments and Toodle-Oots