This old circuit, from the 80's, uses an integrated circuit that is uncommon today. The circuit is intended for loads controlled by triac and the resistors depend on the desired control.
September 2017 - Microchip's MCP6411 operational amplifiers for frequencies up to 1 MHz are in...
This circuit activates a relay by activating one of a series of optical sensors that can be...
This is the circuit of a commercial flash from the 60’s. We found it in a march 1961 Radio...