Using JFETs, this circuit from a 90’s American documentation can generate signals of 0.15 Hz. The JFET can be of any general-purpose type like the BF245 or MPF102.
The existence of field effect transistors at the input of the integrated circuit (operational...
This circuit has a maximum output current of 5 A, and the 2N3055 must have an excellent heat sink....
This circuit is suggested by Motorola and is based on a 1723 voltage regulator. The 2N3055...