This circuit was found in 1967 General Electric documentation. The transistors of the time can be replaced by modern equivalents.
This transistor source can supply currents up to 2 A and the voltage determined by the zener...
The oscillator of this circuit operates around 8 MHz, but the output will be at a frequency three times...
This filter, which uses an operational 741, passes the frequency band from 500 Hz to 1 500 Hz,...