There is a cam at each setting of the gap change gear. When the change gear is at the top
of the cam, the change gear disengages from the gap change gear. At this time, the
armature resets, changing the head gap by one setting.
The head gap is modified in .06 mm units for each range setting.
2-2-03b.tif
Microline 520/521 Service Handbook 2 - 27 Principles of Operation
P/N 59257803