XY-MK-5V RF Transmitter Receiver Module 433MHz Wireless Link Kit

Connect the transmitter module's VCC pin to Arduino's 5V, GND to GND, and DATA to a digital pin (e.g., D12). For the receiver, connect its VCC to 5V, GND to GND, and DATA to another digital pin (e.g., D11). Use the VirtualWire or RCSwitch library to encode and decode data. Ensure you use a common ground between all devices and consider adding a decoupling capacitor near the module's power pins for stable operation. The transmitter can run on voltages from 3.5V to 12V, affecting range.

The rated range is 20 to 200 meters, heavily dependent on environment, obstructions, antenna, and supply voltage. To maximize range, power the transmitter at its maximum 12V, use a proper 1/4 wavelength (approx. 17.3cm) wire antenna soldered to the ANT pad, and ensure a clear line of sight. Elevate both modules, avoid sources of electrical noise like motors or switching power supplies, and orient antennas vertically. The receiver's high -105 dB sensitivity helps, but interference from other 433MHz devices (e.g., car key fobs) can reduce reliability.

No, this specific kit provides only one-way communication as it includes one transmitter and one receiver tuned to 433MHz. For bidirectional communication, you need two kits with the transmitter and receiver pairs operating on two distinct frequencies (e.g., 433MHz and 315MHz). Alternatively, you can use a true transceiver module. For this kit, one Arduino can only send, and the other can only receive. You would need to implement a protocol to alternate control if using two frequencies for simple duplex.

For Arduino, the most common libraries are VirtualWire and RCSwitch. VirtualWire provides robust data encoding with CRC checks, while RCSwitch is tailored for simulating remote controls. In your sketch, initialize the library with the correct data pin numbers, set the transmission speed (typically 2000 bits/s for reliable operation with these modules), and use the send() and receive() functions. For Raspberry Pi, you can use the `433Utils` suite or Python libraries like `Raspberry Pi-rf`. Remember these modules use AM, not digital packet radio, so error checking is not inherent.