This circuit for equipment adjustment and diagnostics was found in a Mullard transistors manual from 1960. Information about the transformers is given with the diagram.
Found in a 90s Popular Electronics, this circuit is interspersed between the filter and the...
This circuit is from an 80's documentation. The integrated circuit is from the time and the...
This circuit was found in a 80s American documentation. The zener diodes determine the points of...