[Milsurplus] PL-259A question

[Jack Antonio]

Hopefully this isn't digging too far deep into
arcane trivia.

We are all familiar with the ever present PL-259.

But what is the story behind the PL-259A? This is
a 3 piece connector, with a back shell held on by a
set screw.

The PL-259 is also known by its Amphenol number of 83-1SP and the Navy 
number of 49190

The PL-259A is known as the 83-1SPN and the Navy number of 49195.

The questions I have,

Did it have a specific application, or intended for
use anywhere a PL-259 was to be used?

Did it solve any particular problem the PL-259 had?

There appears to be available today a modern PL-259A
which is not related to the original PL-259A, my questions
concern the original one.

Thanks

Jack Antonio WA7DIA
scr287 at sbcglobal.net