This circuit was found in a Popular Electronics from the 90s. The circuit has temperature compensation. Coil and capacitors depend on the frequency at which the circuit will be used.
We found this filter in the 1990 Motorola Linear Databook, but it can be implemented with other...
Instead of the lamps, LEDs can be used in series with 470 ohm resistors. The circuit is from an...
This low current solenoid driver was found in an ancient American documentation. The solenoid must be...