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[AMPS] Another "DC Filaments" question/thought..

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Subject: [AMPS] Another "DC Filaments" question/thought..
From: ccc@space.mit.edu (Chuck Counselman)
Date: Wed, 1 Nov 2000 13:14:16 -0500
Mike Baker <k7dd@earthlink.net> wrote:
>    Whilst reading all the thoughts about DC filaments, something
>crossed my mind.  If we use say 6.3VAC as normal filament voltage and
>switch to DC, wouldn't the DC equivalent for heating purposes be .707
>times 6.3v = 4.5955VDC???  or have I missed something?

Yeah.  What you missed is that "6.3VAC" is 6.3 root-mean-square (RMS)
volts, which dissipates the same power in a resistive load as 6.3 V DC.

What you're probably thinking of is the fact that the RMS of a sine wave is
0.707 times the amplitude, or peak value, of the wave.

-Chuck W1HIS



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