[R-390] Mini Mc/Kc Knobs

[Dave Merrill]

Some years ago I got a pile of knobs from an industrial
surplus place that was located in what was then a low
rent warehouse district just north of the Chicago Loop.

In the lot were some that are the same design as the 
R-390x Mc/Kc knobs but smaller in size:

http://www.geocities.com/plutoniac2003/Knobs/Group1.jpg

As you can see from the first photo, two of the three are
about the size of two bar knobs of the R-390x.  Some 
knucklehead (not me!) cut a notch in the larger ones.

Anybody ever see these smaller varieties on military or 
commercial equipment?

Another odd fact is that Doehler Jarvis was also located in
Chicago.  They are the supplier identified on the knob print
from Jeff Adam's R-390 CD.

73,

/dave
N9ZC