1. Using high-quality materials, the frequency stability of products is good; 2. This product can not only output 7.83Hz Schumann wave, but also add programmable frequency modulation technology, which can adjust the frequency in the range of 0.1Hz-30KHz; 3. The frequency reference of digital circuit crystal oscillator is more stable and anti-jamming; 4. The power supply interface adopts DC5.5*2.1 or Micro-USB interface, which is convenient to use. The USB terminal can work when plugged into a charging treasure or USB charging head or other USB power supply equipment. Product description: Shumanbo itself does not directly act on sound or video products to improve the sound quality, but on the spatial environment, so that people's body and mind can be relaxed, the body's perception of sound and images can be improved, the healthy work efficiency of the human body can be improved, and psychological pressure can be relieved. This product can not only output 7.83Hz Schumann wave, but also adjust the frequency in the range of 0.1 Hz - 30 kHz. The frequency reference of digital circuit crystal oscillator is more stable and more anti-jamming. Product parameters: Green compact edition: Antenna waveform: sine wave Interface waveform: sine wave Power supply interface: Micro-USB Power supply voltage: 5V Rated power consumption: Less than 1W Default frequency: 7.83Hz Adjustment range: 0.1Hz-30000Hz Voltage amplitude of sine signal: 3V Voltage amplitude of square wave signal: 5V Change the frequency method: Enter the frequency directly and press the lower left key to complete the setting. For example, press [7][.][8][3] and then press [OK] to set the default power-on output to 7.83Hz, and the setting range is 0.1-30KHz. Note:Due to different printing batches, if there are sligh