This circuit was found in the January 1996 issue of Electronics Now magazine. The circuit is powered by voltages from 10 to 24 V and has a control for the intensity of the output signal.
This circuit can use a pendulum sensor. We found this configuration in a 1994 publication. The...
This circuit is from a 1964 Electronic Design. The sensor is an LDR and the transistors are...
This circuit works both as a preamplifier and activates a relay when speaking in front of the...