They could all be imposters & probably are looking at the numbers over a short distance of coax,
there is no special place to put the meter where you will get a more accurate reading,
either you DON'T have cmc on the braid & any position of the meter will give a true vswr reading minus the loss in the coax you added between meter & antenna,
or you DO have cmc & no position for the meter will give a true reading of the antenna impedance, they are all true at the point you insert the meter,
your just not measuring what you think you are measuring
your are always measuring the antenna in parallel with the coax outer braid common mode impedance regardless of where you put the meter along the coax,
coax length will effect vswr by changing the impedance terminating the antenna end of the coax,
how can that be?
coax has 3 conductors for rf, 2 inside + the outside of the braid,
typical cb installs have a 3 conductor feed-line plus a conductive mast & sometimes a 5th conductor a silly ground wire running from the antenna to a rod in the ground,
not many people think about the 3rd & 4th & 5th conductors,
but they will waste good money on lower loss coax that makes less difference to signal & noise than properly installing your antenna.
think of a vswr meter as been like a fuel gauge in your car that shows the total gallons of ( gas + washer bottle + oil level + transmission fluid ) and displays it as gallons on one scale
but i only want to know how much gas i have,
block the pipes feeding everything but the gas tank,
what you have left on the gauge is what you want to measure & its not pissing oil & water everywhere.
