The operational 714 (not the 741) is an old Raytheon type that is no longer common today. The circuit can be implemented with modern operational. The power supply must be symmetrical.
The frequency depends on the coil and is not found in the original documentation but should be...
This is a device for those who need to show that they know how to use digital electronics but have...
Using an operational amplifier with FET, this circuit from a 1977 publication can generate...