This circuit is from a time when this type of feature was not common in line cars. The pulse transformer has a 1: 1 turn ratio and the SCR admits equivalents.
This circuit was found in ancient American documentation. It provides a 70 Vpp signal at...
The figure shows a Wien Bridge circuit with non-linear feedback. The resistance of the RL lamp is...
Found in documentation for radio amateurs of the 70's, this circuit generates signals from 18 to 24...