Suggested by Motorola documentation from the 1980s, this circuit can be implemented with equivalent power MOSFETs. The type depends on the current of the controlled motor, as well as the diodes.
I found this circuit on a December 1976 Radio Elettronica. The Italian magazine no longer exists, but...
This circuit was found in the February 1993 Radio Electronics magazine. The frequency depends on...
A 25 mVpp applied to the input of this circuit produces in the output a 1 Vpp signal. The...