Register Account

Login Help


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

Latest Topics

Topic Created Posts Views Last Activity
Serious Error in 2018 ARRL Handbook! Mar 16th 2018, 16:25 5 7,411 on 2/5/19

Latest Posts

Topic Author Posted On
Serious Error in 2018 ARRL Handbook! AG6RF on 28/4/19
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:

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

Back to Top


Instragram     Facebook     Twitter     YouTube     LinkedIn