Bill takes apart a smoke detector and shows how it uses a radioactive source to generate a tiny current which is disrupted when smoke flows through the sensor. He describes how a special transistor called a MOSFET can be used to detect the tiny current changes.
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, or even use Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for MakeCode, CircuitPython, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Python for Microcontrollers — CircuitPython takes flight! All aboard with datum, Bluefruit CPX, and more! #Python #Adafruit #CircuitPython #PythonHardware @circuitpython @micropython @ThePSF @Adafruit
Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !
Just for clarity: there are also cheaper smoke detectors out there, that rely on optics to detect smoke – but the presented ones are the better…
The cheapest smoke detectors I see are always battery only ionizing units. The optical units can be better depending on the type of fire. Combination units are available too combining optical with heat or ionizing. I think optical is uncommon for residential devices but more common in commercial installations. Optical beam detectors are used in large spaces like gymnasiums and warehouses where they can be located below the ceiling level for earlier detection.