Well, okay if your talking about the average "magnitude" of the voltage, then
you are
correct, Vavg = 2/pi *Epk = 0.636*Epk = 0.9*Erms. Now I understand what Marv
was
getting at.
73 de Mike, W4EF...........
----- Original Message -----
From: "2" <2@vc.net>
To: "Mike" <W4EF@dellroy.com>; "AMPS" <amps@contesting.com>
Sent: Thursday, June 28, 2001 11:46 AM
Subject: Re: [AMPS] RMS Power
>
> >
> >Hi Marv,
> >
> >The average voltage of a sine wave is 0. That is why the RMS value
> >is used in power calculations. For a sine wave the RMS voltage is
> >0.707 times the peak voltage.
> >
> However, polarity counts for naught when calculting watts. Average V of
> a sinewave is c. 0.636 of E-peak.
>
> cheers, Mike
> >
> >----- Original Message -----
> >From: "Radio WC6W" <wc6w@juno.com>
> >To: <billydeanward@hotmail.com>; <amps@contesting.com>
> >Sent: Thursday, June 28, 2001 7:20 AM
> >Subject: Re: [AMPS] RMS Power
> >
> >
> >>
> >> On Thu, 28 Jun 2001 05:32:16 -0000 "Billy Ward"
> >> <billydeanward@hotmail.com> writes:
> >> >
> >> >[WC6W]
> >> >The Bird 43 (without a peak reading module) is an average reading
> >> >meter.
> >> >
> >> >[Billy]
> >> >I thought that the Bird 43 was an RMS meter without the peak reading
> >> >module.
> >> > RMS and average are not the same?
> >> >
> >> >Billy
> >> >
> >> >_________________________________________________________________
> >>
> >> Hi Billy,
> >> No, they usually aren't.
> >>
> >> For a sine wave, average voltage is equal to .9 * RMS voltage. The
> >> factor is different for other waveshapes. Try figuring the numbers on a
> >> triangle wave for... fun. :-)
> >>
> >> The Bird scale is calibrated to read "power" (RMS voltage squared /
> >> line R) even though it is driven by average voltage... accurate as long
> >> as it is measuring a sine wave in a 50 ohm resistive system as Maury
> >> noted.
> >>
> >> 73 & Good morning,
> >> Marv WC6W
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> *
> >>
> >> ________________________________________________________________
> >> GET INTERNET ACCESS FROM JUNO!
> >> Juno offers FREE or PREMIUM Internet access for less!
> >> Join Juno today! For your FREE software, visit:
> >> http://dl.www.juno.com/get/tagj.
> >>
> >> --
> >> FAQ on WWW: http://www.contesting.com/FAQ/amps
> >> Submissions: amps@contesting.com
> >> Administrative requests: amps-REQUEST@contesting.com
> >> Problems: owner-amps@contesting.com
> >>
> >
> >
> >
> >--
> >FAQ on WWW: http://www.contesting.com/FAQ/amps
> >Submissions: amps@contesting.com
> >Administrative requests: amps-REQUEST@contesting.com
> >Problems: owner-amps@contesting.com
> >
> >
>
>
> - R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.
> end
>
>
> --
> FAQ on WWW: http://www.contesting.com/FAQ/amps
> Submissions: amps@contesting.com
> Administrative requests: amps-REQUEST@contesting.com
> Problems: owner-amps@contesting.com
>
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