#325: Use NanoVNA and Smith Chart to show effect of adding transmission line length @w2aew

Uploaded January 2021 | Updated September 2026, 2 weeks ago

This video shows how adding or removing transmission line (coax) between a transmitter and an antenna affects the SWR and impedance looking into the line. The Smith Chart is used to show how to graphically visualize the result, and then the NanoVNA is used to demonstrate these effects on a real antenna and feedline. Please refer to other videos in my NanoVNA playlist to learn how to setup, calibrate and operate the NanoVNA. Here is a link to my NanoVNA video playlist:
youtube.com/playlist?list=PL4ZSD4omd_AylEyNCQYR3RcEb0olukPEJ
Here is a link to the notes from this video:
qsl.net/w2aew/youtube/EffectofAddingRemovingCoax.pdf

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