[Milsurplus] Re MHz

[Mike Hanz]

The first reference I can find on this came from 
http://www.iec.ch/about/history/ , which says

"In 1930 the IEC (International Electrical Congress) established the 
following electrical units:

Hertz, for the unit of frequency
Oersted for the unit of magnetic field strength
Gauss for the unit of magnetic flux density
Maxwell of the unit of magnetic flux
Gilbert for the unit of magnetomotive force
Var for designating the unit of reactive power
Weber for the practical unit of magnetic flux"

Sounds like that's fairly authoritative, and certainly explains the dial 
marking.

 - Mike