[Milsurplus] K-13 gunsight

[Telegrapher@worldnet.att.net]

I obtained a K-13 compensating gunsight this past weekend.  Excellent
condition but no specs on it.  Google search shows a lot of hits but
nothing technical.  Anyone have any data on it?  Has a single pin
connector for probably voltage of some sort and a couple of receptacles
for some sort of gear drive.  No mount but nothing appears to be missing
or damaged.  

Any help would be appreciated.  BTW, it was evidently used on the waist
gunners position of the B-17 from one source of info.  However i don't
recall ever seeing anything like it in that position.  At least on the
"G" model.  

Larry
W0OGH