This amplifier, from Philips Databook is suitable for automotive applications. The input resistance is 60k ohms and the frequency range is 20 to 20 kHz.
This circuit was found in Philips documentation from 1967. The components are of the time, being...
The Variable Frequency Oscillator (VFO) shown in the figure can generate signals in a frequency...
This circuit uses an operational amplifier to modulate the light emitted by an LED with audio...