This circuit activates a warning lamp when an incoming call is received. We found it in an 80s Hands-On Electronics. The diac and triac can be of any type.
In this oscillator a phase shift network formed by C1, C2, C3 and R1, R3, R4 determine the fase...
For inductive loads we have the configuration shown in the figure. Note that the optical coupler...
This circuit was found in the Linear Applications Handbook by National Semiconductor. It uses...