[Milsurplus] Does anybody remember a torque amplifier?

[Jim Haynes]

I have a mental image from 50+ years ago of a thing painted OD and
having a motor on it, and an input shaft and an output shaft.  It was
called a torque amplifier.  The power was supplied by the motor and
a little bit of effort to turn the input shaft resulted in the output
shaft turning the same amount with a lot more torque.  I guess it had
been used in something like a radar-controlled gun aimer, or maybe
just a manually controlled gun aimer, to allow some low-power control
input to maneuver the output that required a lot more power.  I'm
not at all clear on how the thing worked.

I recently googled for "torque amplifier" but it seems that some
tractor manufacturer applied that term to a low gear so most of
the hits are about tractors and repairing same.

The context of the question is an item on slashdot in the past week
concering a guy who has invented a transmission that is infinitely
variable from reverse to a high forward speed and says that all power
transmission is through gear teeth - no belts or clutches.  So I'm
wondering if he has just re-invented the WW-II era torque amplifier,
or maybe invented a new way of making one.

Or am I just imagining the whole thing?