Sensors
Temperature, humidity, motion, distance, light and air quality. Wiring, the library that actually works, and what the numbers mean once they arrive.
Door Sensor
A TinkerBlock board that takes the two bare wires of a magnetic door or window sensor on a screw terminal and puts it between VCC and SIGNAL. A closed sensor reads HIGH; open, SIGNAL floats, because the board has no pull-down, so you set one in setup(). The red LED lights while the sensor is closed: it is not a power light.
3-Axis Accelerometer
A Silan SC7A20H accelerometer on a TinkerBlock board: tilt, orientation, shakes and drops over two shared I²C wires, at address 0x19, with the pull-ups fitted. 3.3 V only.
SHT31 Temperature and Humidity Sensor
A Sensirion SHT31 on a TinkerBlock carrier: two numbers over two shared wires, calibrated at the factory, with the pull-ups already fitted and two jumpers on the back that set the address and take them away again.
ADS1115 16-Bit ADC I2C Module
Four analog inputs on two wires, with a real 16-bit converter and its own reference — the part you reach for when analogRead is not good enough. Which range to pick, why the supply is the real ceiling, and the two addresses this board can take.
10. Tilt Sensor
Learn the tilt sensor.
12. NTC Thermistor
Learn to read NTC with analog input and do simple conversion; outcome: serial continuously shows raw value (0–1023) and converted voltage (0–5V); values change when you warm the module.
13. Ambient Light Sensor
Learn to read light with analog input; outcome: serial shows light value (0–1023)—cover light and value drops, shine light and value rises.
14. Knock Sensor
Learn the knock sensor; outcome: tap the module and the LED turns on; stop and it turns off.
27. NTC Thermistor Temperature Sensor
Learn to use analog input and the Beta equation to convert NTC thermistor voltage to temperature.
31. I2C Temperature LM75
Use Wire library for I2C to read LM75 temperature; outcome: serial continuously shows temperature (°C); warming the sensor makes the value rise.
33. Steam Sensor
Use analog input to read the steam sensor; outcome: serial shows steam value (0–1023); breathing on the sensor or spraying water vapor raises the value.
36. Piezo Sensor
Use analog input to read the piezo sensor; outcome: serial shows the vibration value (0–1023); a tap makes it jump.
38. Project: Temperature Humidity Display
Project: read temperature and humidity and display; outcome: serial shows temperature and humidity continuously, or 4-digit display shows temperature (integer).
4-Direction Tilt Sensor
One metal roller in a square switch with four corner contacts, on a TinkerBlock board: tip an edge down and the roller joins that side's two lines. Your board finds which pair by holding one line LOW and reading who follows. Four answers and none, no angle, and four red LEDs that light when a line is held LOW.
8. Collision Sensor
Learn the collision sensor.
Ambient Light Sensor
A phototransistor and a 4.7 kΩ resistor on a TinkerBlock board: light makes a current, the resistor turns it into a voltage, and SIGNAL rises with the light. A lit room reads low on the scale, bright light flattens just under VCC, and it sees near infrared best.
Collision Sensor
A lever microswitch with its 10 kΩ pull-down and a red hit light already fitted: SIGNAL reads HIGH while the lever is pushed in. The bumper for a TinkerBlock robot, and the sense that never reports a wall that is not there.
DHT11 Temperature and Humidity Sensor
A DHT11 on a TinkerBlock board, the TK38: temperature from 0 to 50 °C to ±2 °C and humidity from 20 to 80 % to ±5 %, in whole numbers, on one data wire. The 10 kΩ pull-up is fitted, so it is three wires and one library. Feed VCC what your board's pins run at: the pull-up ties DATA to it.
Hall Effect Sensor
An omnipolar Hall switch on a TinkerBlock board: bring either pole of a magnet near and SIGNAL goes LOW and a red light comes on. No contact to wear out, it works through plastic, and it looks at the field every 22 ms, so it is made for doors, lids and slow wheels.
Infrared Receiver
An infrared light sensor on a TinkerBlock board: an Everlight PT334-6B phototransistor in a black 5 mm package and a 10 kΩ load, so SIGNAL is an analog voltage that rises with how much infrared arrives, steady or flashing. The partner of the TK63 for a break-beam. It is not the TK15 IR Receiver: it decodes no remote, and the TK15 ignores steady light.
Infrared Speed Sensor
A GK105A slotted optical switch on a TinkerBlock board: an infrared beam across a 5 mm slot, judged by an LM393 comparator. Something in the slot reads HIGH; a clear slot reads LOW and lights a red LED. Put a slotted disc through it and count pulses for rpm, up to about 1,900 a second. VCC must be your board's logic voltage.
Knock Sensor
A spring vibration switch with its 10 kΩ pull-down, a 100 nF capacitor and a red flash light already fitted: SIGNAL goes HIGH for a moment each time a knock swings the spring onto its rod. A tap on a table as a button, a door that was knocked, a box that was dropped.
Linear Hall Effect Sensor
An SS49E-type linear Hall sensor on a TinkerBlock board: an analog voltage that rests at half of VCC with no field and moves about 3.25 mV per gauss at 5 V, up for one pole and down for the other. It tells you how strong a magnetic field is and which way it points. VCC must be your board's logic voltage, and it is not a current sensor on its own.
LM75 Temperature Sensor
An LM75B digital temperature sensor on a TinkerBlock board, read over I2C at address 0x48: two bytes that are already degrees, in steps of an eighth, within 2 °C from −25 to 100 °C. VCC goes to your board's logic supply because the pull-ups end at VCC.
NTC Thermistor
A 10 kΩ NTC thermistor in a divider with a fixed 10 kΩ: SIGNAL is half of VCC at 25 °C and falls as it warms. Read it on any analog pin and turn it into degrees with two lines of arithmetic.
Piezo-Ceramic Sensor
A 22 mm piezo disc on a TinkerBlock board that needs no supply: two wires, GND and SIGNAL. A tap makes a hump on SIGNAL that rises in about a millisecond and drains in about a tenth of a second, taller for a harder tap. It senses change, not weight, and nothing on the board holds SIGNAL below 3.3 V.
Reed Switch
A glass reed switch on a TinkerBlock board: two blades that a magnet pulls shut, from either pole, with no power needed to sense. It sits between VCC and SIGNAL with a 10 kΩ pull-down, so a magnet reads HIGH, and a red LED lights while it is closed. It draws nothing while open, and VCC must be your board's logic voltage.
Reflective Optical Sensor
A Vishay TCRT5000 on a TinkerBlock board: an infrared emitter that is always on and a phototransistor beside it, both looking out of the front. Infrared coming back pulls SIGNAL down from VCC through 4.7 kΩ, so white paper reads low and black tape or open air reads high. Analog only, best at 2.5 mm, and VCC goes to your board's logic voltage: 3V3, or 5V on an Uno.
Steam Sensor
A TinkerBlock board that reads water on its surface: seven nested loops of bare gold, every other one on VCC, the rest held at 0 V by a 1 MΩ. Condensed steam, breath or a drop across the loops makes a divider, and SIGNAL rises from 0 V towards VCC. It is an analog output, it does not sense humidity in the air, and VCC must be your board's logic voltage.
Tilt Sensor
An SW-520D ball tilt switch on a TinkerBlock board: two steel balls in a brass can that close the switch when its lead end, the board's left edge, is the lower one. It sits between VCC and SIGNAL with a 10 kΩ pull-down and a 100 nF, so left edge down reads HIGH, and a red LED lights while it is closed. It draws nothing while open, reads nothing definite near level, and VCC must be your board's logic voltage.
TinkerBlock Ultrasonic Distance Sensor Kit
Distance by echo timing, five to a pack — enough for a robot with a sensor on every side.
Ultrasonic Distance Sensor
Distance by echo timing, on an RCWL-9616 that runs from 3 to 5 V and speaks GPIO, I2C, UART or 1-Wire, chosen by two solder jumpers. No divider on a 3.3 V board. Soft and angled surfaces are where it quietly lies to you.
DHT22 Temperature and Humidity Sensor
A DHT22 on a TinkerBlock board, the TK39: temperature from −40 to 80 °C to ±0.5 °C and humidity from 0 to 100 % to ±2 %, in tenths, on one data wire. The 10 kΩ pull-up is fitted, so it is three wires and one library. Feed VCC what your board's pins run at, and read it no more than once every two seconds.
Read a sensor
Wire a DHT22, read it reliably, and send the numbers somewhere you can see them.
Put a DHT22 on the internet in 20 minutes
Wire a temperature and humidity sensor to an ESP32-S3, and watch the readings land on a live dashboard you can open from your phone. No backend, no server, no port forwarding.