We found this circuit in a 1965 General Electric documentation. The circuit generates synchronized 400 Hz pulses. Modern components can be tested.
When the sensor, an ordinary photo-transistor, receives light, the relay closes its contacts. The...
We found this circuit in a 1972 documentation. The transistor, in fact, is a unijunction that can...
This circuit is from a 2010 publication by Texas Instruments. The circuit interfaces a...