For example, press [7][.]. [8][3], then press [OK], it can be set to 7.83Hz default power-on output 7.83Hz, setting range 0.1~30KHz. The product not only can output 7.83Hz Schumann wave, but also can adjust the frequency in the range of 0.1Hz ~ 30KHz, digital circuit crystal oscillator frequency reference, more stable, stronger anti-interference.
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