This circuit was obtained from Linear Technology documentation from the 80's. Powered by 5 V it can be used as a shield. The components are from the era.
This circuit came out in a 1978 American publication, but can be assembled with transistors BC547 or...
The components of this filter are calculated using the formula f = 1 / RC and it can be...
This common circuit with two transistors was found in an old French publication. The supply can be...