The magnetospheric generation and propagation characteristics of ion cyclotron waves associated with a Pc 1 emission observed by a network of four middle and low-latitude ground stations are determined using ground source location techniques and ISEE 1 plasma data. The source region at L=4.7¿0.7 is determined from propagation in the F2 region ionospheric duct using wave polarization characteristics at ground stations. This source is just inside the steep plasmapause seen by ISEE 1 at L=4.9¿0.1. The ion cyclotron wave packet interhemispheric bounce period measured from the ground spectra increases with time from 140 to 155 s during the event but is in agreement with dispersion calculations undertaken using ISEE 1 electron density and cool to cold ion composition data in a H+ plasma with 8--10% He+ and <1% 0+ ions. The frequency of the Pc 1 emission band seen on the ground (0.5--0.8 Hz) corresponds to the propagation region between the equatorial 0+ cutoff frequency and the He+ cyclotron frequency. Linear convective growth rate calculations inside the plasmapause show significant wave amplitudes in this band. With these results it is possible to completely describe the wave generation mechanism and the magnetosphere ionosphere propagation characteristics for the Pc 1 event. ¿ American Geophysical Union 1989