Digital humidity-temperature meter with analog display

Measuring temperature and humidity is really easy as there are many convenient sensors. Usually to measure humidity along with temperature there are combined sensors used like SHT21. Arduino even have libraries to get things working right away. ff you want to display things there are more options and of course more work to do. Normally digital sensors are reflected in digital displays, but sometimes we like to look things old fashioned. So in this case analog display can be used. Kerry D. Wong built such device with couple analog displays where one indicates temperature and another humidity. Analog displays are custom made where arrows are controlled with couple servo motors. Driving servos with Arduino is also easy so overall code in project takes only few lines of code. It is set to take readings every 0.5 seconds. Temperature scale ranges from 50 to 95 degrees Fahrenheit and humidity from 5% to 95%.   Continue reading

Arduino displays min and max temperatures

Arduino is a great way to do simple projects like this because it doesn’t require lots of messing with making PCBs and interfacing. Simple project can be done by attaching things directly and or by using protoboard. In this project Arduino reads temperature values from LM35DZ temperature sensor via analog input 0. To display min and max temperature values there are a LCD attached in 4 bit mode. Of course it also shows current temperature. So it may be convenient to set it for some certain time to see what the temperature change was during 24 hr. Continue reading