This traditional circuit generates a 200 Hz sinusoidal signal. The frequency depends on the capacitors and the transistor can be a BC548. We found this circuit in a 1979 documentation.
This timer has a divider programmed by BCD switches. The circuit is from a Radio Electronics...
Using a mechanical drive motor, this circuit was found in old documentation. The engine turned off the...
When the input voltage exceeds the value set in R4, the LED lights up, indicating this. The...