Found in a Popular Electronics from the 90s, this game can be seen in other configurations on this site. The circuit uses components that are still common today.
When the sensor connected to points A and B is activated, removing the ground from the base of Q1...
This oscillator was found in the 1994 National Instruments Linear Applications Handbook. The...
With the circuit shown in the figure, the frequency of a 5 MHz oscillator controlled by crystal can...