Crumbs, a blast from the past! I never did get my amateur license mainly down to that Morse code defeated me
but I was for years doing SWL
. Somewhere I still have a bunch of SQL cards from places around the world.
So in regard to "G" the G as I recall means Great Britain registration but I think I recall reading that G followed one a particular number digit was seen as desirable....cannot recall which number it was but a bit like car number plates there were only so many variables available!
PS wracks brains ~ I think G6 ones were dedicated to those who were registered as licensed for a particular high frequency spectrum area?