Transistor gain meter (CB20522E)

This circuit was found in a publication in the 1950s, mainly applying to germanium transistors of the time.

5 W Amplifier - TIP31-TIP32 (CB1005E)
This excellent amplifier with complementary symmetry output stage was taken from one of my audio...
TC35678 CI Low Power Bluetooth
May 2017 - Toshiba's new Bluetooth Low Energy Chip TC35678 for wireless applications can be...
Remote listening amplifier (CB21957E)
Today we can call this circuit a baby monitor. It is a microphone amplifier found in a publication by...