The loss attributable to a 2:1 VSWR can be stated as a constant,; the reflection loss from a 2:1mismatch is 0.512dB. Wwhat is variable is the loss before the incident power hits the mismatch, and what happens to the 0.11% of the incident power that goes backdown the cable, some of which is re-reflected again back up the cable from the transmitter. Those are cable type dependant.
73
Jeff G8HUL
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[email protected]Subject: Re: [nanovna-users] Dipole antenna with Low Z0 feed point Impedance
Joe
The loss attributable to a 2:1 VSWR cannot be stated as a constant. It is a function of the length and characteristic loss of the coax cable used.
The additional loss in 100 feet of cable that is a consequence of having a 2:1 SWR load would be 0.33 dB for RG58 and about 0.11 dB for LMR400. This is far less than 11.1% however none of the calculated additional loss are significant and overcoming those losses by searching for a perfect match will solve no problem that the author is experiencing.
Warren Allgyer - WA8TOD
