The question is as follows:
An interfering signal from a transmitter is found to have a frequency of 57 MHz (TV Channel 2 is 54 - 60 MHz). This signal could be the:
And the options are as follows:
A) crystal oscillator operating on its fundamental B) second harmonic of a 10 metre transmission C) seventh harmonic of an 80 metre transmission D) third harmonic of a 15 metre transmission
Now in my mind options B and D are the same frequency as the second harmonic of a 10 meter transmission is 30 MHz*2=60 MHz and the third harmonic of a 15 meter transmission should be 20 MHz*3=60 MHz. I don’t see how one answer could be more correct than the other.