I realize this is a long shot, but here goes....
I'm looking for the Ten-Tec Argonaut 509, serial number 509-4580. It
had green LEDs replacing the dial lights and a couple of diodes back to
back tacked on the SSB generator board to provide some RF clipping. Back
in my freshman year in college, my dad gave me that rig. I had a lot of
fun with it, but then in my lean grad school years I traded it at TNT
Radio in Minnesota for a shiney new Icom IC-735. If you have any info
on this perticular radio, please send me a note!