DHT22

The DHT22 is a basic, low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin (no analog input pins needed). It's fairly simple to use, but requires careful timing to grab data. The only real downside of this sensor is you can only get new data from it once every 2 seconds, so when using our library, sensor readings can be up to 2 seconds old.

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WiFi NodeMCU ESP8266 Google Clock

“A simple easy WiFi clock using “Google” timestamp, with temperature and humidity. Oct2020 update: bug fixing and automatic brightness I made several clock with arduino but was looking simple, easy, light, synchronized in real time with internet clock different than …

Honda Motorcycle Dash

“This is my attempt to build an information display / dashboard replacement (or additon) for modern Honda motorcycles. It connects to the bike via its diagnostic port and reads information directly from the ECU It also contains a GPS module and …

Yet another dot matrix clock

“NTP synchronized dot matrix clock showing temperatures and humidity.. Optionally the time source can be GPS. That is what some readers may think, what? Another dot matrix clock? In order to combine inside/outside thermometers with a nice and precise …

COVID-19 and PM10 Levels!

“Experimental studies would assert the possibility that PM10 may act as a “carrier” for the spreading of the viral infection of COVID-19. Experimental studies would assert the possibility that particulate matter may act as a “carrier” for the spreading …

Freezer Failure Alarm

“The other day I started thinking about our chest freezer and all of the hundreds of dollars worth of food that we have in there. What if it fails and goes unnoticed for a while? The freezer is getting older …

An ESP8266-based Temperature, Humidity and Line Voltage monitor

“As anyone who reads this blog probably knows, I have a bit to do with the operation and maintenance of the Northern Utah WebSDR - a remote receiver system that allows anyone with Internet access and a web browser to listen …

Pandemic Dayclock with Indoor Air Quality Sensors

“Pandemic DayClock, with temperature, humidity, and CO2 sensors. With web interfaces to access the data (HTML/XML/JSON). Also OTA update capability. I saw https://hackaday.com/2020/04/08/what-day-is-it/ and printed both the hemisphere clock and pointer. I …

Humidity Sensor Calibration

“This experiment will reveal ability measuring of Humid sensor DHT22, SHT21, BME280. Also mention about how to calibrate them I’ve got 3 sensors that can measure relative humidity of the air: BME280, SHT21, DHT22. They stated ability of measuring …

Build an Inhouse IoT Air Quality Sensor - No Cloud Required

“Build a full-functional small IoT device to monitor inhouse air conditions without using cloud services. The quality of the indoor or outdoor air depends on many sources of pollution and also by the weather. This device captures some of common …

BT LED Matrix Display - 80x8 Px Arduino Based

“In this guide I will show you how to make your own Arduino LED Matrix display! In this project I decided to make my own PCB that is based on Arduino UNO microcontroller - Atmega328p. Bellow you will find the electronic …