This circuit found in a 1964 US publication reverses the signal level by providing 9 to 0 V outputs from 0 to 9 V signals. Transistors may be equivalent.
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....