This low noise microphone preamplifier circuit was found in American documentation from the 90s. The circuit requires special care with the layout. The power can be between 9 and 18 V.
With this circuit, a relay can be activated from an alternating signal with frequency up to a few...
With this circuit the visually impaired can easily locate important places inside the house, such...
In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The...