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Due to the potential for new diagnostic capabilities, there has been renewed interest in the generation of ionospheric stimulated electromagnetic emissions (SEEs) near the second harmonic of the pump frequency (ω₀), a process known as second harmonic generation (SHG). Observations of SHG during experiments at the High Frequency Active Auroral Research Program facility in whichω₀was stepped near the third harmonic of the electron gyrofrequency, 3ω_ce, and the transmit power linearly increased over the heating cycle at eachω₀, were reported recently. A key observation was the linkage between SEEs within ±30 Hz ofω₀, due to stimulated Brillouin scatter, and within ±30 Hz of 2ω₀. This current work reports further High Frequency Active Auroral Research Program observations that compare the time evolution of SEEs including SHG under the following two transmit power conditions (I) linear power ramp (II) maximum available power (2.8 MW). During these experiments,ω₀was stepped near 3ω_ceand also 2ω_ce. The results show that SEEs within ±100 Hz ofω₀and 2ω₀are both suppressed within a few seconds when the ionosphere is irradiated with the maximum available power. These SEEs appear to be suppressed before the onset of field‐aligned irregularities at the upper hybrid layer which is not in line with previous reports. Thus, other mechanisms, which are discussed, could possibly be responsible for the observed suppression of stimulated Brillouin scatter and SHG. Some preliminary diagnostics are derived from the SHG spectra temporal evolution by leveraging concepts from the field of laser plasma interactions.