This high voltage circuit was found in a 1970 documentation. The integrated one is of the time and modern equivalents can be tested. The resistors of the voltage reducing system must be calculated.
This interesting intercom circuit was obtained from an Argentine publication from the 1970s....
This circuit was found in a 90s Popular Electronics. The components are from the era. R3 must be...
This circuit is from an old publication, but it can be assembled with modern components. We can...