Having recently seen the suggestion that …
Most tools and most derivations of SWR will produce negative SWR reports because they are more interested in mathematics than in measurements you can make with a simple RF volt meter.
…, this article explores the expected voltage on a practical transmission line under two mismatch scenarios, voltage that ought be measurable with a simple RF voltmeter.
VSWR concepts… by the book
Textbooks on transmission lines often introduce the concept of standing waves by presenting a plot of voltage along a mismatched lossless transmission line.
Above is a plot of calculated line voltage vs displacement from the load, -ve is towards the source. Continue reading Cooking the books on VSWR