This circuit was obtained from a 1965 Radio Electronics. The semiconductors used admit modern equivalents. The high voltage coil is an automobile ignition coil.
This high Q “rejector” or notch filter rejects signals whose frequencies are in the range...
This circuit was found in documentation from the 90's, having an LC compensation network. The...
This two-transistor circuit was found in the January 1994 issue of Electronics Now magazine....