This interesting circuit was found in a 1968 documentation. The transistor can be a general-purpose equivalent. The circuit can act as a shield.
Indicated by Popular Electronics to be used with a car headlight, this circuit can also have...
In this circuit of a 1970s publication, data from the coil to oscillate at the desired frequency...
This circuit was obtained from a Philips documentation from 1968. The transistors can be replaced...