Bias oscillator for tape recorders (CB7339E)

This circuit was found in a 1967 Electronics World. The circuit uses components of the time that are difficult to obtain, such as the transformer.

| Clique na imagem para ampliar |

One Pulse Per Second Generator (CB20136E)
This circuit was found in documentation from the 80s. It is based on unijunction transistors not...
DC PWM Motor Photocontrol (CB11855E)
The speed of the motor connected to this circuit depends on the amount of light that strikes the...
Optical isolator (CB8272E)
This sensor circuit from a 1967 Ferranti documentation uses components from the era. The circuit...