DIYbanter - View Single Post - Converting low resistance pot to high resistance ?

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wrote:
Meat Plow wrote:
On Sun, 17 Dec 2006 17:59:35 +0000, N Cook Has Frothed:

Over the years I've often done the opposite by putting a resistor between
wiper and low end and another from wiper to high end.
just in case I've missed something over the years is there a way of say
converting a 20K pot to a 100K pot, with full range from bottom to top ?

No.

How can you make a 100k pot when youve got a variable R that only
covers 20k. The answer is you cant. But there are 2.5 buts:

1. if its a ganged pot its poss to put the 2 tracks in series, doubling
R. But you cant then have a tapoff that moves anywhere along that track
length. However in many apps its ok to use a 2 terminal variable R, so
this will sometimes do.

2. You may be able to cut the track width down to increase R. Lot of
hassle though!

3. Some ccts can be tweaked so they run happily with a lower value pot.

But in these days of material overflow, its hard to think of any reason
to do any of the above now.

NT

or lots of cuts across the track 2/3 of the way on alternate sides will
convert a straight track into a wiggly hence longer and higher R one.
All depends if youre in a shop or holed up in pow camp.

NT