Features: 1. This product is made of high quality materials, using low temperature drift crystal oscillator and high precision DAC special chip, the frequency stability of the product is good; 2. This product not only can output 7.83Hz Schumann wave, but also added programmable frequency modulation technology, can be adjusted in the range of 0.01Hz ~ 100000Hz frequency; 3. 2 kinds of specifications, with no shell and with shell 2 kinds can be selected according to demand; 4. Digital circuit crystal frequency reference, more stable, stronger anti-interference; 5. Power supply interface using Type-c interface, easy to use, support Type-c to Type-c power supply. Product Description: Schumann wave itself is not a direct role in the sound or video products to improve sound quality, but the role of the spatial environment, so that people's physical and mental relaxation, improve the body's perception of sound and images, improve the health of the human body to improve the efficiency of the work of the human body, and alleviate the psychological pressure also has a better effect. The product can not only output 7.83Hz Schumann wave, but also can be adjusted in the range of 0.01Hz-100KHz frequency, digital circuit crystal oscillator frequency reference, more stable, stronger anti-interference, the use of low-temperature drift crystal oscillator and high-precision DAC special chip, you can accurately output the frequency and pure sine wave. Product Parameters: With acrylic shell version: Operating voltage: DC 5V (DC 4-15V) Working current: 9-14mA Power supply interface: Type-c (support Type-c to Type-c power supply) Default frequency: 7.83Hz Adjustment range: 0.01Hz~100000Hz pure sine wave Signal voltage amplitude: 3V With 3.5MM audio output connector With acrylic case Size: 155*105*26MM (with shell) Product list: 1X signal generator 1X Acrylic case