Sinusoidal Oscillator 741 (CB8426E)

Found in a 90s Popular Electronics, this circuit uses a 741 to generate frequencies from 0.1 to 30 Hz. Observe the phototransistor feedback.

| Clique na imagem para ampliar |

DC to DC converter 555 (CB15024E)
This circuit doubles the input voltage, converting, for example, 6 V and 12 V. The output current is...
5 V x 200 mA regulator with the LM105 (Cb14083E)
The LM105 integrated circuit consists of a voltage regulator integrated in a metallic enclosure. The...
7W amplifier CA3020 (CB18501E)
The CA3020 integrated circuit was one of the first commercial types, sold in the 1960s. The...