Eddie,
the best way to tell what the swr of an antenna is supposed to be is to see what type of connector the radio uses and what coax is recommended, thats what it is supposed to be the same as, but in real life and the real world that's rarely if ever the case,especially if you want it to cover more than one frequency.
the swr is a consequence of the antenna design, for a cb they are all supposed to be 50 ohms, but in reality only one i know off, the starduster type will give you that straight off from its design, others will give you it from their design plus matching devices, some just dont need it to be perfect 1.0:1 to work well, and trying to match antennas that are close as dammit to 1.0:1 from their design is pointless, much better to tune it for resonance and accept a slightly higher swr reading imo, 1/4 wave whips and 1/2 wave dipoles are two classic examples, although if you want to be really pernickity you can alter design slightly or add reactance of one type to neutralise reactance of another type, be it capacitive or inductive. some people who get a perfect 1.0:1 match on an antenna thats not meant to be 50 ohms have introduced reactance therefore mistuning resonance for their particular desired frequency, the majority get it from using shitty lossy coax that gives lower readings due to cable losses and fuck all else,
it never ceases to amaze me the look on peoples faces when i install better coax like rg214/u and not only does their swr go up, so does their performance and their noise generally drops too. i've even known some dumbasses undo what i did and go back to their old shitey signal just to see 1.0:1 swr. then they have the cheek to wonder how i can talk to the world on an hp 4000 with mil spec coax that shows true swr and i couldn't give a fuck if its below 3.0:1, cause its too fucking cold here to get oot the car to adjust it for a fucking minimal gain noone will ever notice except ma fucking frostbitten fingers.
