This circuit is from a 60's documentation. The capacitance C1 can be between 20 pF and 0.01 uF depending on the generated frequency. Equivalent transistors may be employed.
This preamp version uses BC109 transistors that are older versions of the current BC549 in plastic...
This circuit was obtained in a technical documentation from the 70s, but it can be assembled with...
This stepper motor control was originally designed to use a PC's parallel port and is quite simple...