This cassette player motor speed control was found in the January 1991 issue of Radio Electronics magazine. The circuit is for voltages from 9 to 12 V.
The 1 kHz Wien bridge oscillator presented was found in the 1993 Linear Technology Applications. The...
Originally this circuit is from an English magazine, but I found it in Argentina's Radio Chassis...
The circuit is a multivibrator version using two NPN general purpose transistor. This circuit can...