7.83Hz Wave Generator with Sine Square Inverted Square and Sawtooth Waveforms

Frequency Generator Device 0.001Hz-200kHz Range with 13 Waveforms and Keypad

Frequency Generator with 13 Waveforms 7.83Hz Default and Programmable Timer

7.83Hz Frequency Generator with Programmable Modulation and Waveform Selection

Schumann Wave Generator Adjustable 0.1HZ~30KHZ Sine+Square+Inverted Square Wave

Schumann Wave Generator Adjustable 0.1~30000Hz Sine+Square+Inverted Square Wave.