This interesting circuit for analog TV selects the first line of a frame. The circuit was found in a 1967 Electronic Design. A modern equivalent transistor can be tried.
This circuit was obtained in a 1975 documentation. It is intended for old vehicles that still use...
With this circuit it is possible to select transistors and their compliant test. Or circuit...
This power supply circuit with selectable voltages was found in the June 1979 issue of Radio...