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AG6RF

Joined: Wed, Dec 13th 2000, 00:00 Roles: N/A Moderates: N/A

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Serious Error in 2018 ARRL Handbook! Mar 16th 2018, 16:25 5 1,920 on 2/5/19

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Serious Error in 2018 ARRL Handbook! AG6RF on 28/4/19
@W1VT
THERE IS STILL AN ERROR IN THE 2019 HANDBOOK!!!
The sign of the argument of the third component should be negative: (fC-fM), not (fC+fM)

I have a hard time believing that this error is there in the first place. This equation is the FUNDAMENTAL EQUATION OF RADIO.
Please FIX IT! It's not even in the 2019 errata page.

Errors like this bring all the technical details in question.

Serious Error in 2018 ARRL Handbook! AG6RF on 19/3/18
Great! Thanks.
Serious Error in 2018 ARRL Handbook! AG6RF on 16/3/18
In the 2018 Handbook, on page 11-3, second column, an equation is given for an AM signal with fC carrier and fM modulating signal. It's the sum of three expressions, one for the carrier, one for the upper sideband, and the third for the lower sideband, as explained in the text that follows.

But the sine functions for both sidebands are shown as the same: 2π(fC + fM)

Also, the arguments for the sideband terms are missing time, t.

So, it should read:

Csin(2πfCt) + ((C*M)/2)sin((2π(fC + fM)t) + ((C*M)/2)sin((2π(fC - fM)t)


Check the Wikipedia page Amplitude Modulation: https://en.wikipedia.org/wiki/Amplitude_modulation

This is a pretty serious error, as this is the fundamental equation for radio. I'm surprised it got in there.

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