From: Keith Wootten
Subject: Re: circuit wanted-SQUARE PULSE GENERATOR
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Date: Tue, 26 Nov 2002 12:30:15 +0000
NNTP-Posting-Date: Tue, 26 Nov 2002 12:30:26 GMT
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In message <email@example.com>, Tony Williams
>In article ,
> Keith Wootten wrote:
>> My feeling is that 1024 steps, should give an adequate simulation of a
>> ten-turn pot, being 102 per revolution. Any gotchas?
> I have done measurements on high-quality 10-T
> pots and 35mm dials (the biggest in the RS cat).
> When used as a potentiometer, the control linearity
> is about 0.05% of full scale, and the tightest
> setting resolution is about 0.025% of full scale.
> When the dial mechanics/scale is added in, then
> 0.1% overall setting accuracy is on, but only just.
Thanks for that, Tony, looks like 1024 steps is in the right cricket
ground. Linearity isn't much of an issue for my application.
If I were to go with real pots, I'd use a dial mech, but really only for
the locking capability - these are bridge zeroing pots and the actual
pot position don't make no never-mind. A lockable 'ordinary' knob would
do just as well, but I can't recall ever having seen such a thing, only
the collet lock things for screwdriver slot adjustments.