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Analysis of magnetospheric Pc 1 and Pc 2 (in brief Pc 1–2) pulsations at a network of six northern hemisphere stations at latitudes 65°–76° CGM shows that their average frequency decreases with increasing latitude of the station. Their maximum occurrence is at L=6–9 and 1200–1600 LT. The ionospheric ducting is weak for f < 0.3 Hz. Occasionally the Pc 1 intensity at a station is modulated by a simultaneously arriving quasi‐periodic Pc 4–5 signal. A mechanism for generating micropulsations which is common to both high‐frequency and low‐frequency waves is presented and discussed, the proposed mechansim being that a broadband signal from the solar wind is amplified in the magnetosphere in the frequency bands of the field line resonance (Pc 4–5) and in the He+ cyclotron frequency (Pc 1–2) range.

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