We found this circuit in the 1957 Raytheon transistor application manual. The transistor can be a BC558 and the common 6 V relay, just by using this voltage in the supply.
The circuit we have just described has been mounted in the car of the author of the project for...
This circuit was found in an old European publication, but it can be implemented with more modern...
This circuit is based on a PLL 566 and generates positive ramps. The frequency depends on Rx and C...