“I was trying to figure out why this 3-way adapter produced half-wave rectified DC in opposite polarities on the “low” and “medium” setting when my scope ground touched one of the wires and let the smoke out. The blown component appears to be a “quadrac” (combined diac and triac in a single package) in an old TO-105 case. The circuit seems to just put a diode in a series for “low” and a diode going the other way with a non-adjustable triac dimmer in parallel for “medium”.”
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.