[sdiy] Re: Stocking the House...

[Ian Fritz]

At 03:18 PM 5/19/06, Larry Troth wrote:
>Newbie type question: What ARE the most common values for SDIY??
>
>I'd like to build up a stock as well, and I'd rather get a bunch of 1%'s at
>2, 3, or even 4 times the price of 5%'s, but just get quantities of values
>I'll actually use.  (Somehow, I don't think there are really 100 different
>values that I need on a regular basis.)

Larry --

I usually stick with the standard 10% values, as they have been widely used 
in past designs, and can usually get you close enough to target design 
values. 12 values for each decade:

1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, and 8.2.

For starters you probably only need to go from about 100 Ohm to 4.7M.

You can get these in 1% precision, and you might as well go for 50ppm 
tempco as well.

You can make up in-between values if you need them by series or parallel 
combinations.

Beyond that, it's handy sometimes to have values that differ by convenient 
ratios.  So, for example, you might also add 2.0 and 4.99 (closest 
available to 5.0) to the above series to give yourself the 1, 2, 5, 10 
sequence.

   Ian