I'd put something like 100V across the field winding and see what the output
is for the armature when turned at a speed near the rated speed.
The thing that is nice about DC motors is that the can be used easily as DC
generators, especially if the field is a magnet. The other thing about DC
motors is that they will spin on much lower voltages (10^ os rated voltage
is a good starting point for low speed operation) although the current will
be the same approximate valuee as the full speed current. Currrent, of
course, goes up with load from some value which may be 50% of the max
current.


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Why do penguins walk so far to get to their nesting grounds?