We address deviations in the source bearing of natural pulsed extremely low frequency (ELF) radio signals (Q-bursts) in the Schumann resonance band. The model of smooth day – night non-uniformity is used. The observer is located at the Ukrainian Antarctic station “Akademik Vernadsky” (65.25° S and 64.25° W), and the source is positioned at the same meridian at latitudes of 20° S; 25° N, or 85° N. The equinox period is considered when the solar terminator line is coincident with a meridian. Thus, the source – observer meridian and the terminator meridian are separated by an angular distance varying with the local time of observer. The propagation parameters of ELF radio waves were computed using the full wave solution in the form of Riccati equation for the ambient day and ambient night profiles of mesosphere conductivity. The field spectra were found from the 2D telegraph equations (2DTE). Spectra of the source bearing and of the polarization coefficient were computed for different local times. The source bearing and the polarization coefficient do not exceed ±15° and ±0.35 correspondingly. The Q-bursts in the time domain were computed at the output of an example Schumann resonance receiver. Phasors of the Poynting vector were used for estimating the source bearing in the time domain. Maximum deviations in the source azimuth may reach ±4° directed toward to the midnight point. The eccentricity of the “elliptic” magnetic field phasor may reach 0.1. Impact of the day – night non-uniformity is comparable with that of the continuous Schumann resonance background. Therefore, terminator effect is detectable in records of extra-powerful Q-bursts exceeding the background noise by the factor of 10–20.

我们解决了舒曼共振带中自然脉冲极低频 (ELF) 无线电信号 (Q-bursts) 的源方位偏差。使用平滑的日夜不均匀模型。观测者位于乌克兰南极站“Akademik Vernadsky”（南纬65.25°和西经64.25°），源位于南纬20°的同一子午线上；25° N 或 85° N。当日光终结符线与子午线重合时，就考虑了春分周期。因此，源 - 观察者子午线和终止子午线之间的角距离随观察者的本地时间而变化。ELF 无线电波的传播参数是使用全波解以 Riccati 方程形式计算的，用于中间层电导率的环境白天和环境夜间剖面。场谱是从二维电报方程 (2DTE) 中找到的。计算了不同本地时间的源方位和极化系数的光谱。源方位和极化系数相应不超过±15°和±0.35。时域中的 Q 突发是在示例舒曼共振接收器的输出处计算的。坡印廷矢量的相量用于估计时域中的源方位。指向午夜点的源方位角的最大偏差可能达到±4°。“椭圆”磁场相量的偏心率可以达到0.1。昼夜不均匀性的影响与连续舒曼共振背景的影响相当。所以，