Amplifier with different output (CB9057E)

This circuit was found in a 70s National Semiconductor manual. It has a different output way for coupling to the speaker.

Nanoammeter (CB12009E)
This circuit allows the measurement of very weak currents indicated on an analog instrument or...
Preamplifier with tone control (CB9517E)
Found in National Semionductor documentation this circuit combines a tone control with an...
RF Generator (CB7424E)
Found in a 73 magazine from the 1980s, this circuit generates signals from 3.2 to 22 MHz. FETs can be...