Rca1948FrequencyModu.. - The New Jersey Antique Radio Club

MODULATION BY ELECTRON BEAMS 499tional to the total beam current and inversely proportional to the cavityvolume and the square of the resonant frequency.The maximum loadingoccurs when w = (1 — k) a = 0. For a transit angle differentfrom zero this occurs at k = 1, i.e., u> c= , which means that theelectron circular motion is exactly in resonance with the electric field.As seen from Figure 13, Ao> is zero at this point, so that the electroncurrent is entirely a resistive component.When the transit angle is not too small the loading is essentiallyzero atW = (1 — k) a = Sir (99)since T(w) is zero at this point and T(u) is very small. In this casewe find that minimum loading occurs at (1 — k) a = Zir, instead of 2-n-