74HC14 and different valued pots

[themadscientist]

I'm ordering the parts suggested from an earlier post

http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8
&safe=off&threadm=4064f078.850025%40news.highstream.net&rnum=9

and had a quick question. What would be the difference if I used a 1MEG
pot over a 10K pot or vice versa? Is a lower resistence better in this
application?

Thanks.

 

[Beau Schwabe]

On Thu, 08 Apr 2004 15:12:04 GMT, themadscientist <none@none.com>
wrote:

I'm ordering the parts suggested from an earlier post

http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8
&safe=off&threadm=4064f078.850025%40news.highstream.net&rnum=9

and had a quick question. What would be the difference if I used a 1MEG
pot over a 10K pot or vice versa? Is a lower resistence better in this
application?

Thanks.

The higher the pot value, the lower the frequency or number of counted
pulses. You can compensate this by reducing the capacitor value in
the RC circuit. Accuracy is going to depend on the min/max frequency
range you set by your RC values, the computers ability to distinguish
individual pulses, and the amount of cpu time you are willing to burn
counting pulses. You will need to experiment to determine an optimal
range for your application. I would recommend building this on a
solder-less bread board before you do any hard wiring.



Beau Schwabe