[TowerTalk] TIC Potentiometer

Zivney, Terry 00tlzivney at bsu.edu
Thu Apr 3 22:17:42 EDT 2014

I seem to recall K1TTT said the earliest rings used a pulse counter instead of the pot.  The implication being that the pulse counter approach had problems and was upgraded to the pot.

A basic problem with putting the whirling magnet on the motor shaft is that it only counts how many times the motor shaft turns.   But, many of he rings appear to skip or slip or miss a beat (whatever you want to call it). So, the ring location is computed by counting the number  of rotations of the motor, not the rotations of the ring.

In my case, the pot reliably follows the motor and the spur gear that is supposed to drive the ring.  The problem with inaccurate readout is not
caused in these cases by the pot but rather by the spur gear and ring 
gear losing contact from time to time.

It seems that is also the case with the ring in the recently posted YouTube video of a  TIC ring problem.

A pulse counting technique that is counts motor revolutions is not inherently superior to a precision potentiometer geared to that same motor.  The selected pot is a ten-turn pot which has lots of resolution potential (sic).   

Terry N4TZ

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