I remember back in 1996 after i saw for the first time “Twister”, i was so hooked on ways to measure weather parameters by myself. APT reception of weather satellites, VLF radio, temperature monitoring… you name it, my backyard was filled with antennas, each one bigger than the other. Now when i found this awesome weather station project all those memories returned and my soldering station is heating up.
This weather station measures the most important weather parameters: temperature, pressure and relative humidity. You can select to view temperature in Celsius or Fahrenheit degrees and pressure in mbar/hPa or mmHg. The station can also measure the temperature from a remote location using RX,TX433 wireless modules.
The data is displayed on a LCD along with the date and time, the highest and lowest temperature in the past 42 hours and a graphical histogram. To increase its autonomy the weather station has a sleep mode, it wakes up only to gather the data from the sensors, memorize it and display it. Looking at the schematic you will see it uses MOSFET transistors as switches controlled by the PIC18F452 to power up sensors and RX/TX modules to preserve battery life.
Operation of the weather station is done using the three buttons. One button brings the menu and the other two are used to navigate in it, or too navigate through memorized data. Pressing any of these buttons will awake the station from its sleep mode. Another thing to mention is that the data will not be lost if the station loses power.
The sensors used are MPX4115A for pressure measurement, TC77 SPI for temperature and H1 sensor takes care of humidity reading. The H1 outputs a capacitance so its used with a 555 oscillator, whose frequency depends on the humidity reading. PIC18F452 is the brain of the receiver station and PIC16F84 takes care of the transmitter.
All schematics, PCB layouts, hex files and source codes are available in the project.
Monitoring Weather: [Link]