This circuit of the 70's uses transistors of the time. The circuit can amplify signals from 10 Hz to 100 kHz and modern equivalent components can be used. The circuit is from Ferranti.
This 12 or 13.8 V stabilized source is suitable for experimental FM transmitters that require...
This circuit uses a TL071 to differential amplify the signals from a microphone and thus reduce...
Found in Motorola documentation from the 90's, this circuit charges the capacitor with a constant...