Re: Mother Very Easily ...

On Wed, 14 Dec 2005 04:42:20 +0000 (UTC), in message
<dno7rc$nko$1@xxxxxxxxxxxxxxxxx>
sethb@xxxxxxxxx (Seth Breidbart) caused electrons to dance and
photons to travel coherently in saying:

>Robert Sneddon <nojay@xxxxxxxxxxxxxxxxxx> wrote:
>>In message <slrndptg2i.hoe.dmsilev@xxxxxxxxxxxxx>, Daniel Silevitch
>><dmsilev@xxxxxxxxxxxx> writes
>>
>>>What about tighter-tolerance resistors? I know that you can do a lot
>>>better than 1% if you are willing to pay the price premium.
>>
>> The precision rating will be printed on the safe-box the armed guards
>>deliver by helicopter along with the certification from the National
>>Standards Laboratory.
>
>I can understand how manufacturing a resistor to a given tolerance
>might be difficult, but surely measuring one is simple enough?

Except for the wirewound jobs, they're usually manufactured to
common standard and then _tested_ for tolerance. It's easy to
manufacture resistors to 20%; the better-tolerance ones are
individually _tested_, and the ones that test to within 1% of
nominal value are relatively rare. You can, however, buy a bunch
of cheap resistors and test them yourself, if you want.

>(And there are some cute tricks to get the measurements of resistors
>to more accuracy than your measuring device has, if you're willing to
>do the work and arithmetic.)

First you have to build the Wheatstone bridge.

--
Doug Wickstrom <nimshubur@xxxxxxxxxxx>

"We find two great gangs of political speculators, who alternately take
possession of the state power and exploit it by the most corrupt ends-the
nation is powerless against these two great cartels of politicians who are
ostensibly its servants, but in reality dominate it and plunder it."
--Friedrich Engels

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.

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