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.
This circuit can be used as a control shield for microcontrollers of all types. The supply is made...
The figure below shows an AC transconductance amplifier with the National Semiconductor LM3900. The...
This circuit provides a good audio power from a signal at least 1 V of amplitude. The MOSFET must...