This different circuit was patented and described in the Radio Electronics magazine of March 1958. In that section it used to present different configurations that received patents.
This power supply with transistor regulation was obtained in a 1995 documentation. The power...
This two-station intercom was found in documentation from 1966. R4 should be experimentally...
We found this circuit in a publication from 1966. The components are from the period. Complete...