Ok, you win. The Booby prize. Enjoy your word games and make sure that you keep showing your ignorance.
-- Service to my country? Been there, Done that, and I\'ve got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida
you can't measure RMS instantaneously either.
Bye. Jasen
If you know the frequency, the simultaneous measurement of V and dV/dt will give you the answer.
Graham
===================================== What's ASD mean? Is that some Strine slang like 'Gday'? Oh... sorry, Mr Phil would never utter the words 'Good Day'. As for MASSIVE ignorance, we all seem to have our strong and weak points. One of your strongest points seems to be your uncanny ability to belch up an epithet at anyone that you perceive to have any difference of opinion from you on any subject, political, electronics, religious. Do you have the complete Quaran memorized word for word? That would be the obsessive compulsive behaviour I would expect from you. I bet you were the top of your class in the Mullah's Islamic school of love and tolerance. I love you brother Phil.
This is a bloody stupid argument anyway; being able to measure something instantaneously is wholly irrelevant. But...
How would you expect to measure dV/dt with a single sample?
Tim
"Tim Auton"
** So long as the wave is sine shaped, the dV/dt wave is also sine shaped.When the original wave peaks, dV/dt goes through zero & when the original wave goes through zero, the dV /dt wave peaks. An RC network ( ie 6dB /oct HPF) can easily be designed to derive the matching dV /dt wave in *real time* for a input wave with known characteristics.
A steady sine wave voltage of given frequency has a unique dV/dt at any point in time - so it follows that if both V and dV/dt are known for a point in time, so is the steady voltage.
....... Phil
Or even DC, really. Not without allowing some settling time for the needle or the ADC.
give
try that on a staircase,
-- Bye. Jasen
"jasen"
** Try hurling yourself down one -you PITA,
dead sheep shagging,
ASD f***ed,
Kiwi BLOODY IDIOT !!!
........ Phil
On 23 Aug 2006 07:52:24 GMT, in message , jasen scribed:
Precluded by the "Mean" part of the term, wouldn't you say?
I can easily calculate the RMS value of a single, instantaneous voltage measurement. Very easily.
John
=============================== OK, you've got my attention. Just don't make Phil cuss me out anymore. I can't take it. I'm an only child. Very sensitive.
You need to know f first.
An 'instantaneous' measurement of V and dV/dt will tell you all you need to know about the magnitude of a sinusoidal waveform.
I don't understand how JL can do it with a single measurement unless he knows the phase angle too.
Graham
-- He can\'t. No matter what, at least two measurements will have to be made, which blows Larkin\'s hypothesis out of the water. >
The RMS value of a *single* voltage measurement...
Tim
-- That depends on knowing the shape of the waveform before the measurement is made. Sinusoid? One answer. Square wave? A different answer. In any case, Larkin, if you don\'t know the waveshape of the incoming signal and you have to wait until you can figure out what it is, your claim that you can calculate the "RMS value of a single, instantaneous voltage measurement" is specious.
This thread descended into pedantry a little while ago, in case you hadn't noticed :)
Read carefully. John never said he could measure the RMS value of an arbitrary waveform from a single voltage measurement.
Tim
========================================== I was hoping I'd get a little backup from some mathematician when I said since the voltage was a function of time, it only had one value at any instant in time, and thus my assertion that 'peak to peak' was not a mathematical quantity like a vector or scalar etc etc. But noooooo.... just jump all over the poor programmer........ tough bunch. I'm just waiting for old Phil to slip up.....
"BobG" = Groper from Hell
( snip nauseating SHIT from this anencephalic)
** FUCK OFF !!you ASD f***ed TROLL !!!!
....... Phil
=========================================== Any Aussies care to step up to your buddy here and explain his 'Strine to me? Is a Groper Someone Who Gropes? Like a dirty old man that cusses a lot? Down at the end of this thread I asked him what he meant by ASD, but I though I had given him such a dressing down that he was too shamed to respond. Silly me. As for being a Troll, you think I actually TRIED to get a rise out of you just for fun? I guess I'm just a troll and you Phil are some sort of Grand PooBah of electronics. Funny Hat and everything. Now don't forget your pills before you go to bed! You get very grumpy!
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