Lets settle this Harmonic question right now.

Discussion in 'General Technical Questions and Answers' started by NO9N, Jul 30, 2020.

1. NO9NHam MemberQRZ Page

I was talking to a friend on the air about harmonics the other day and he was adamant that the first harmonic of a frequency was the fundamental frequency x 2. I was taught that the first harmonic was the fundamental frequency x 1. Which is it?

A Fundamental Waveform (or first harmonic) is the sinusoidal waveform that has the supply frequency. The fundamental is the lowest or base frequency, ƒ on which the complex waveform is built and as such the periodic time, Τ of the resulting complex waveform will be equal to the periodic time of the fundamental frequency.

Is this question answered wrong? I looked immediately for 7.1 MHz or 7100 KHz but its not there.

2. WR2EHam MemberQRZ Page

@NO9N

The first harmonic is the fundamental.

Isn't answer B " 7,100 KHz " ?

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3. KL7SGXML SubscriberQRZ Page

7.1 Mhz (B) is the first harmonic/ fundimental frequency. I checked "Electromagnetic Compatibility Engineering", By Henry W. Ott; and, it is not expressly stated that the fundimental frequency is the first harmonic. But, the graphs clearly show this to be the case.

4. KB7WGHam MemberQRZ Page

The question with that selection of answers is wrong. If the fundamental is 7.1 mhz, then all harmonics will be mhz, not khz.

Most people refer to the first harmonic as the fundamental. It is confusing, calling the fundamental as the 1st harmonic, but they do. But a harmonic is suppose to be an integer multiple of the fundamental.

And the fundamental times the integer 1, is the fundamental. See how that works? When ever you have problems understanding things and following thru something........it is usually because of the math terminology.

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5. K3RLDHam MemberQRZ Page

But doesn't 7.1 MHz = 7100 kHz?

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6. WR2EHam MemberQRZ Page

I don't understand what you're saying...

Isn't 7100 (or 7,100) KHz the SAME frequency as 7.1 MHz ?

(oops, doubled with RLD!)

Last edited: Jul 30, 2020
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7. WA4ILHSubscriberQRZ Page

Seriously, Harmonics are also calculated to measure mechanical movement such as vibration in a railroad car truck. (wheels)
Tom WA4ILH

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9. KB7WGHam MemberQRZ Page

Review the question. 7.1 mhz is not 7.1 khz.

10. K3RLDHam MemberQRZ Page

It's showing "7,100 khz", not "7.100 khz". As we are in the USofA - "7,100 khz" is indeed equal to 7.1 MHz.

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