Modulated infrared emitter (CB7251E)

Found in a 1968 Mullard manual, this circuit can function as an infrared audio link. The transistors can be the BC548.

| Clique na imagem para ampliar |

Stabilized Amplifier (CB24235E)
This general purpose two-transistor complementary configuration was found in the December 1972...
Transistor Driver MC34071 (CB14482E)
The two circuits are from Motorola's Linear Databook from 1990. The resistors depend on the gain...
Megaphone (CB994E)
This circuit works only with carbon microphones, due its low impedance. The speaker should be good or...