This project describes a DIY wireless temperature and humidity monitor for kids’ or infant’s room using the Arduino platform, and inexpensive and easily available ASK transmitter/receiver modules. On the transmitting end, an Arduino nano senses the ambient room temperature and humidity using the DHT22 sensor and transmits the data to a receiving end Arduino over a 433 MHz ASK RF link. The receiving side Arduino decodes the received bytes and displays the information on a LCD screen. The indoor range of the RF transmission is about 100 ft, which is mostly sufficient for a decent size house.
Things you will need
You will need the following items to build this project.
- ASK transmitter/receiver pair
- Two Arduino boards. I am using an Arduino Nano on transmitting side and Arduino Uno on receiving end.
- One Nokia 5110 LCD for displaying data at the receiving side
- One DHT22 sensor for measuring temperature and humidity at the transmitting en
- Two LEDs and two 330Ω resistors
- Wires, breadboard, prototyping board, etc.
Few words on ASK RF kits
There are varieties ASK Tx/Rx modules available online in both domestic and international markets (specially China). Some of them come with spring antennas, and some don’t. With the ones without antennas, you can connect ~20cm wire to their antenna pin on circuit board. The figure below shows some of the ASK RF modules you can buy on eBay and Amazon.
For more detail: Wireless temperature and humidity monitor for baby’s room