It's a Qiahip 433mhz Wireless Wide Voltage Coding Transmitter Decoding Receiver 4 Channel Output Module For 433Mhz Remote Controls
Specification
- : Negative power supply
+: Positive power supply, DC 3-24V
K1: External input keys, short to ground start transmitting data to 1, the A button on the remote control.
K2: External input keys, short to ground 2 start transmitting data, the equivalent of the remote control B button.
K3: External input keys, short to ground start transmitting data 3, the equivalent of the C key on the remote control.
K4: External input keys, short to ground 4 start transmitting data, the equivalent of the remote control D keys.
ANT: transmitting antenna