[time-nuts] TAPR "PulsePuppy" Pot Selection

[Brian, WA1ZMS]

I have seen similar issues to Dana's and have told myself it must be torque left in the gear-train within the pot. Maybe all in my mind as well, but it seems real to me on some equipment.

-Brian, WA1ZMS

> On Dec 24, 2017, at 5:26 PM, Dana Whitlow <k8yumdoober at gmail.com> wrote:
> 
> I think I need to clarify what I mean by "backlash".  It is not simple free
> play in
> the adjustment mechanism- it is something much more irritating, as follows:
> 
> I sneak up on the desired result, but manage to overshoot slightly.  So I
> back
> off on the screw, and find that at first the result continues to change in
> the
> *original* direction (making the overshoot even worse) for a bit before
> finally
> reversing as I wanted it to.  This behavior is not conducive to having a
> good
> time making critical adjustments, nor does it lend any confidence in the
> stability
> of the adjustment in the face of handling.
> 
> Dana
> 
> 
> On Sun, Dec 24, 2017 at 4:06 PM, Charles Steinmetz <csteinmetz at yandex.com>
> wrote:
> 
>> John wrote:
>> 
>> I didn't really notice much backlash, though when setting oscillators I
>>> try to approach (slowly) from one direction until it's "good enough" and
>>> then stop, to avoid that problem.
>>> 
>> 
>> The hot tip is not to just "sneak[] up on the sweet spot and then walk[]
>> away," as Dana put it.
>> 
>> Anytime you have an adjustment with some hysteresis (classic example is
>> setting a d'Arsonville movement to zero), you want to sneak up to the
>> perfect setting and then run the adjuster *back* the way you came just a
>> touch, to leave the adjusted part on its own without any mechanical
>> connection to the adjustor mechanism.  Such contact is almost always the
>> culprit if the adjustment drifts after you set it.
>> 
>> This takes some "feel" for the motion of the adjuster mechanism, but it is