Despite being transistorized, this is a constant current source circuit for 1 V valve filaments such as the 1H4 tube.
This circuit triggers a warning oscillator if you forget the lights on when you leave the car. The...
The twin-T oscillator simulated here produces damped oscillations when excited by short sqare...
Epson SG 8018 Epson Crystal Programmable Oscillators Available from Mouser Electronics, these...