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Many phenomena in the high‐frequency pumped ionosphere exhibit dependence on the pump beam incident angle α. This motivates a systematic study of the α dependence of the stimulated electromagnetic emission (SEE), particularly near electron gyroharmonics. We report the first observations of stationary SEE spectra for α ranging from −28° (north) to 28° (south) at three receiving sites, for the pump frequency (f0) sweeping near the fourth gyroharmonic (4fc). The following is established: (i) For pumping near the magnetic zenith (α = 7°, 14°, 21°), when existent dynamic broad upshifted maximum in the SEE spectrum indicates that artificial ionization layers are excited, suppression of the downshifted maximum at f0 ≈ 4fс is weakest, and 4fс increases. (ii) Weaker similar effects occur for α = −14° (a condition called “mirror magnetic zenith”). (iii) For northern pump beam inclinations, the SEE intensity decreases (in comparison with southern inclinations and vertical), most strongly at the southernmost receiving site.

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