Turn Your Power Supply into an Ohmmeter - It's Free!

Yup.

BTW, LEDs are far more complex than you might think . I once had one that flickered randomly at low current yet worked fine at 30 mA .

Was a blue RS LED, FWIW .

They behave strangely at low currents - I also had the "LED hysteresis" effect , where it turns on at a higher current than it turns off . This was on a damaged red LED .

Reply to
Andre
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"Sir Charles W. Shults III" wrote in news:OFFRa.122068$ snipped-for-privacy@twister.tampabay.rr.com:

Now your getting logical and there is evidently no room for logic in this thread.

Reply to
buck rojerz

"Sofie" wrote in news: snipped-for-privacy@corp.supernews.com:

My goodness! FINALLY! An intelligent reply! At least somebody is using their head, instead of the other end.

Reply to
buck rojerz

Hey, with this new fangled Newer Math, It wouldn't surprise me. I'm still getting used to the idea of three Ohm's Laws.... :)

Reply to
William Hayes

but

Dead Banana. ( beating a dead horse dry )

After all, you are calling "the" English [ liars. ]

They coined Potential of Current to Flow = current * resistively of length/area while Temperature is constant as Ohm's Law. E = I * R Voltage = Current * Resistance

"The" English named it after George Ohm.

What part did you fail to grasp ?

material is ohmic or not.

So a Cross Sectional Area of a 00awg Cable has the same ohmic value at

20,000 feet as a 24awg cable at 20,000 feet ? Surely I'm missing your point.

vs I curve.

Using what gauge of certain material ? Using what Temperature Conditions ?? Ever seen a P4 Processor smoke when a fan is not applied to it after a few minutes of run time ??

dimensions are--even if the cross section varies from point to point.

If the curve is straight, even if the curve is straight. This means your processor can not function. It is breaking your Ohm's Law.

you know Ohm's law

I understand the resistive linearity of certain materials that conduct electrons verses certain materials that do not conduct electronics and each has a chart that relies heavily on the Gauge of the material and Temperature.

vs I curve.

I have a conductor made of air, using 240,012 volts of potential energy flow, you claim I can determine the plot of Voltage verses Current. Without having to know the gauge of the air or temperature and why either has an effect on the current flowing between the potential energy flows. Benjamin Franklin wrote several papers regarding such flows. You'll find them interesting.

Reply to
William Hayes

??? I have not idea what you mean by the above.

Who are these "English" people you refer to? A lie is a willful statement contrary to what one knows to be true. I never called anyone a liar here. Mistaken perhaps, but not a liar.

What is "Potential of Current to Flow"? Current exists, it does not flow. Charge flows.

I know that the MKS unit of resistance was name after George. And George stated that for some materials, the current is proportionate to the voltage. I don't know who named that material property after him, do you?

Whatever you are talking about above.

Yes, you certainly are. I am saying that whatever shape the material is does not affect whether it is ohmic or not. I never said that same length cables with different diameters made out of the same material will not have different resistance values.

V

Doesn't matter. No matter what the shape of the conductor, a V vs I curve can be plotted.

Nope, why should that matter?

Law.

Don't let your mind wander. We are talking about Ohm's law applied to solids, not to computers.

then

each

The resistive linearity is a property of the material that relies on no chart whatsoever.

V

Without

Benjamin

A volt is not a unit of potential energy per se. Remember charge flows, current doesn't, current just exists. Anyway, sure you can measure the voltage and current of an arc with the right equipment and safety precautions. What does does gauge and air temperature have to do with that? Ratch

Reply to
Ratch

NO NO NO NO NO!!!! You could put some of your LEDs in the holes where the meter leads go, make them blink or change colors or something, and pass the thing off as an experimental DMM that uses leds instead of leads - it reads the circuit by reflected light! And the only difference is the letter a :-)

Seriously - it might be a simple repair. As far as the grungy case - I have on old Fluke 8022 B whose case was filthy. I took the guts out and washed the thing in a bucket of hot water with dishwashing soap. I let it soak for a couple of hours, then scrubbed it with a scrub brush. Came out clean as a whistle.

Reply to
ehsjr

Ohm's Law states that the current in a conductor is proportional to the potential difference across its ends.

I=V/R is an equation *deriving* from Ohm's Law, having decided upon an arbitrary constant of proportionality called resistance.

The concept of resistance *arises out of* Ohm's Law.

IME, it's a lot easier to teach that way, too.

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Reply to
Fred Abse

Volt-amps refers to AC. It's just the product of voltage and current without paying any attention to phase. True power (watts) may or may not be the same depending on the nature of the load, if it's resistive, watts = VA, if it has a power factor not equal to unity, true power is less than VA. VA only equals true power where voltage and current are in phase, ie PF=1.

This brings up the conept of reactive volt-amperes, aka (wrongly) "wattless power"

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Reply to
Fred Abse

Yup, seen it.

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Reply to
Fred Abse

No no no no no... you've got it all wrong... L - E - D. Not le[a]d. ;-p

Tim

-- In the immortal words of Ned Flanders: "No foot longs!" Website @

formatting link

Reply to
Tim Williams

In article , snipped-for-privacy@outerspace.org mentioned...

If it wasn't for all the rat turds......

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Watson A.Name - 'Watt Sun'

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