HiLetgo 315Mhz RF Transmitter and Receiver Module link kit for Arduino/ARM/MCU/Raspberry pi TX Working voltage: 3V-12V. Working current: 20-28mA. Resonance mode: sound wave resonance (SAW). Modulation mode: ASK /OOK. RX Working voltage: 5.0VDC. Static current:4MA. Working principle: single chip superregeneration receiving.