Most base loaded mobile antennas like the Wilson, also have a matching section built into the coil. This provides the ability to achieve a perfect 50 ohm load. Center loaded antennas do not have impedance matching capabilities. Those antennas can only be adjusted for resonance and will not correct an impedance mismatch without the shunt coil at the base.
This is also the case with all unloaded 1/4 wave antennas like a 102 inch whip. The 36 ohms you are seeing is normal. Don't worry about it as the match is close enough and will not cause you any problems.
Glad I read Donalds answer,was about to tell you basically the same thing, your wilsons,sirios etc with SO239 mounts are shunt fed/dc grounded,meaning the base coil is tapped at the 50 ohm point and base of coil will be at rf ground potential, same way a silver rod or 5/8 wave would be.
1.2:1 vswr on a 1/4 wave with zero reactance (ie ,resonant) is a bit low,I'd expect 1.3:1 or 1.4:1, but most likely down to a combination of coax that's a bit lossy,an mfj that's not known for sheer accuracy and a cab that may well be a bit less than perfect counterpoise.
Irrespective both antennas as Donald says are fine for use.both will perform with a barely noticeable difference as would a similar sirio or full 1/4 wave whip, there really is very little to choose between them all in everyday performance and everyday noise conditions, I certainly wouldn't hesitate to use any of them.
You got it lucky,many would murder to see readings like that.Far too many people are hung up on this perfect 1.0:1 swr pish,its unnecessary mythology propagated by the ignorant.Many radios will happily chug awy for years on end into a 3.0:1 swr, some with more rugged ouputs like motorola mrf 477 will happily tolerate 10.0:1 swr all day long,
most amplifiers will easily cope with 2.0:1 swr indefinately and higher swr for a little less time,depending on design and ruggedness off transistors/valves used.
If I see a swr of 2.5 or less,even when using an amp and a randomly stuck on sirio hp4000 with mag base, there ain't no way in hell I'm moving my ass back into the arctic glaswegian air to fix it,fuck that,I'll plug away wae confidence wae heaters at full belt, amp on level 4 and a wee joint to take my mind off how shite scotland really is,especially under another unwanted tory govt, swr's the last thing on my mind,didn't stop me working 54 countries fae the mobile and not one an activation in just over 8 months,
I don't doubt many others have had far more success in less time with similar working conditions and better propagation conditions than I had at the time,which were modest to decent but far from brilliant.
P.s. In 30 odd years of radio,of which about 6 months at the most involved not using amps I've never ever blew an amp or radio power transistor, despite fixing loads for other people that thought screwing an extra couple of watts no-one will ever notice was a good idea.I was busted once when I was 16 for overdriving an amps input with a dirty signal but it made me go learn how to avoid it in future.
