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On Mon, 1 Jan 2007 13:49:22 -0500, "Tom Biasi"
<tombiasi@********optonline.net> wrote:
>
>"kontiki" <mrphyt2@xxxxxxx> wrote in message
>news:1167675894.310573.269430@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>>
>> kontiki wrote:
>>
>>> Hi, does anyone know where a reference table of parallel resistors
>>> could be found?The table is very useful for quick accurate resultant
>>> resistances (to two places of decimal), the tables I've got are from
>>> Practical Electronics Jan. 1990? and have faded to the point of being
>>> unusable.Most non-standard resistance values are easily ascertained
>>> e.g.for 17 ohms->75//22
>>> quickly and easily!
>>> with thanks,
>>
>>
>> thank you for your replies....the "math" is fine,....
>> lets say I want to shunt a 120k res. to get a
>> 15.6k how long does it take to find the required value? a table is much
>> faster ,and if you are limited by values "at hand" again an alternative
>> pair is easily/quickly chosen.This is useful for establishing the
>> practical effects of temperature compensating resistors and
>> thermistors.
>> I tend not to fire up the pc each time I need to do the math...
>>
>Sounds like you may have missed the point. If you plan on doing this sort of
>thing often you really should learn the calculation. It only takes a few
>seconds to make the calculation, you don't need to 'fire up' the pc.
>Reminds me of the checkout girl in the local market; if the machine doesn't
>tell her how much change to give me she is totally stuck.
>
>Tom
Given a list of available resistance values, it doesn't take "a few
seconds" to evaluate possible paralleled pairs that would hit some
target to some tolerance. It could take an hour.
John
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