Rca1948FrequencyModu.. - The New Jersey Antique Radio Club

—:VARIATION OF BANDWIDTH 79the aperture covers the entire bar. As the aperture moves on, thesignal decreases linearly until it reaches the previous constant value,and remains constant until the next bar is reached. If this wave formisused to modulate the frequency of a carrier wave, the variation ofthe phase angle will be 2ir times the integral of this curve of Figure14, as shown by Figure 15. The equation for this frequency-modulatedwave becomese = E sin {mt + S(t)}=E sin at cos S (0 + E cos