It sounds like for what you are looking for you will have to make
something up from parts. A vernier knob turns counter with a center
knob marked with perhaps a degree wheel to count the increments
of each turn and a larger separate outer circumference dial that turns more
slowly to count the individual turns 1-2-3 etc.
If such a turns counter was availiable these days I'm sure the seller would
want a ridiculous price for one IE Surplus Sales of Nebraska.
There is a place that has 6:1 vernier drives for a 1/4" shaft input
on each end, newly made in the USA and in stock for $11.50 each.
Go to their PARTS section and look up vernier drives. I know some
people gang two of these together for a 36:1 reduction which
would be close to what you are looking for. Then you would have to
figure out some way to couple the second shaft drive back up front
to turn the outer circumference dial marked 1-2-3-4 turns up to 36 turns.
Plus you would need to couple off the front center knob for the actual
drive to the roller inductor and vacuum caps. Perhaps a small toothed
belt drive off the front shaft would work here. I bet the coupling could
with a little ingenuity.
73 Todd WD4NGG
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