[cbenham]

Originally Posted by damen

Anybody know what this is??? http://salem.craigslist.org/clt/1401714341.html

I've seen this before but can't find a picture of it. I think it is a piece of test gear used for adjusting the mark-space ratio for frequency shift key shortwave radio transmitterequipment. I looked in some really old books on shortwave including a 1948 Amateur Radio Handbook. #:^(

Cliff