What the genius of Calibration

[loosewire]

An ohm meter you short the leads together and ajdust to zero.
Who discovered calibration and what does it stand for. How many
types of curcuits can you list that need calibration.Are calibrations
a parts of designing a curcuits. What happen to fine tuning your
radio dial, was it design or f.c.c.-Does space flight have calibrations
Are there still signal generators that produce continueous signals
thru the spectrum.Is there calibration in the chip world of compondants.
What type of curcuits and why.

[nsaspook]

Originally Posted by loosewire

An ohm meter you short the leads together and ajdust to zero.
Who discovered calibration and what does it stand for. How many
types of curcuits can you list that need calibration.Are calibrations
a parts of designing a curcuits. What happen to fine tuning your
radio dial, was it design or f.c.c.-Does space flight have calibrations
Are there still signal generators that produce continueous signals
thru the spectrum.Is there calibration in the chip world of compondants.
What type of curcuits and why.

There are calibration standards for everything. Most are traceable to these guys. http://ts.nist.gov/MeasurementServic...s/Services.cfm

For semiconductors most primary standards are sourced from here. http://www.vlsistandards.com/

I handle most ISO/TS calibration audits at work. It's a hell of a lot of paperwork and very expensive.

[rjenkins]

Calibration basically means adjusting the circuit or whatever to do what you want.

As an example, if you made a LED bar VU Meter to display an audio signal level, you would include some facility for adjustment so you can make the full scale display correct for the actual maximum level of the analog signal it's working from.
That is a form of calibration.

For a voltmeter, it would be adjusting to give an accurate reading of the actual voltage being measured.

It's not specific to electronics, all forms of measuring device are calibrated to some extent, such as a micrometer for measuring small objects or a the gas company meter that they use for billing.

[nsaspook]

Originally Posted by rjenkins

Calibration basically means adjusting the circuit or whatever to do what you want.

As an example, if you made a LED bar VU Meter to display an audio signal level, you would include some facility for adjustment so you can make the full scale display correct for the actual maximum level of the analog signal it's working from.
That is a form of calibration.

For a voltmeter, it would be adjusting to give an accurate reading of the actual voltage being measured.

It's not specific to electronics, all forms of measuring device are calibrated to some extent, such as a micrometer for measuring small objects or a the gas company meter that they use for billing.

AUDIT HAT ON

Calibration does not mean adjustment. Calibration is comparing a measuring instrument of unknown accuracy to a measurement standard (traceable) of known value and uncertainty. Adjustment of the unknown instrument is a possible option to reduce the error to within the stated tolerance of the instrument.

International vocabulary of basic and general terms in metrology (ISO, 1993):
"A set of operations that establish under specified conditions the relationship between values of quantities indicated by a measuring instrument or measuring system, or values represented by a material measure or a reference material, and the corresponding value realized by a standard.
Notes: 1. The result of a calibration permits either the assignment of values of measurands to the indications or the determination of corrections with respect to indication.
2. A calibration may determine other metrological properties, such as the effect of influence quantities.
3. The result of a calibration may be recorded in a document, sometimes called a calibration certificate or a calibration report."

http://www.agilent.com/metrology/cal_or_verify.shtml

[Bill_Marsden]

I managed to serve a year in a metrology lab, which gave me a bare taste of it. I did the factory floor test equipment, next door was our standards lab, which calibrated or made sure the equipment we used was calibrated (as in sent to the national labs).

It's funny, in many ways the better you can measure the less accurate everything seems. Not true, but it seems that way, because you can quantify the error.