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congobongo
01-11-2004, 07:01 PM
If a diagram calls for a 1K pot, can a 2K pot be substituted and ony used between open and 50% ? I would like to do the 2600 composite mod but I only have 2K pots. Thanks.

FABombjoy
01-11-2004, 09:17 PM
If a diagram calls for a 1K pot, can a 2K pot be substituted and ony used between open and 50% ? I would like to do the 2600 composite mod but I only have 2K pots. Thanks.

Open and 50%? What do you mean by that?

You can use a 2k, but you won't have as precise of control over the value. It'll probably be all right.

omnedon
01-11-2004, 10:02 PM
Congo asked me first, and i wasn't sure.

By less precise control, you mean that since the 2K pot has a broader range, the precision adjustment will be less. If he was to locate a 1K pot, he may find his (lets say brightness just for the sake of this explanation) 'sweet spot' easier to locate, than if he uses a 2K pot, correct?

I want to understand this too. :)

jonjandran
01-11-2004, 10:38 PM
Well it's been a while since Electronics 101 but here goes.

A pot is a variable resistor.
A 1k pot is 0-1000 ohms and a 2k pot is 0-2000 ohms.

So if you use a 2k pot you can add twice the resistance to the circuit. SO let's say you're using it for a brightness adjustment , you would be able to add twice the resistance to a circuit thereby reducing the electrcicty in the circuit thereby allowing for a much darker setting.

So theoretically a 2k pot would work fine but you would lose a little sensitivity because every turn of the pot is applying twice as much resistance as a turn on the 1k pot would.

Hope I remembered that correctly. @_@

DogP
01-11-2004, 11:16 PM
It all depends on the pot... it should work fine, as long as you can get the same range that you needed from the 1k pot, and that the circuit won't be damaged by having too much resistance (accidentally turning the knob too far). But, you should measure the resistance with a multimeter at full one way and full the other way, because not all pots go from 0 - #, some have a minimum value (to protect from short circuiting), and the easiest way to find out is just measuring it.

DogP

congobongo
01-12-2004, 08:59 AM
Thanks for the response and apologies for my ignorance. What I meant by open to 50% was a range of 0 - 1000 ohms would be 50% of a 2000 ohms pot's range. From your responses, I think it's worth trying given the lowest resistence of the pot is 0. I will let you know what happens, thanks again.

omnedon
01-12-2004, 09:34 AM
This forum exists to expose and then illuminate ignorance. This thread is yet another shining example! :D

bargora
01-13-2004, 05:11 PM
Please note that pot discussions properly beong in the "Happy Hours Pub" forum, as do discussions about the practical applications of Dremel tools to custom water pipes...

rbudrick
01-13-2004, 06:19 PM
The ahppy hours pub...is that still around? Do I not see because I'm not privileged or something?

-ROb