We report here new observations on topside sounder ionograms from the Canadian ISIS II satellite of proton cyclotron echoes associated with the fQ3 resonance. Proton cyclotron echoes were first observed on swept frequency ionograms from the Canadian Alouette II satellite. The echoes occur on the ionograms at nearly constant apparent ranges which correspond to the proton cyclotron period at the satellite. The echoes were first found to be associated with the fundamental resonance of the electron cyclotron frequency, fH, and later reported at the 3fH and 4fH resonances. The new observations were made on ionograms when the satellite was located in regions with low dip angles less than 8¿. This paper will present and discuss the features of these new proton cyclotron echoes, such as the presence often of two echo images, and possible generation mechanisms. A comparison with various ray-tracing calculations by Muldrew (1972a,b) suggests that these proton cyclotron echoes may occur when the particular waves responsible for the fQ3, 3fH and 4fH resonances interact with protons energized by the satellite antenna. ¿ American Geophysical Union 1995