The circuit uses a fast Norton amplifier in a configuration that excites a 75 ohms line. The circuit is suggested by National's 1994 Linear Applications Handbook.
This basic configuration can be found in a lot of articles on this site. In this case, the relay...
This high pass filter was found in the February 1996 Electronics Now magazine. The circuit...
Found in General Electric documentation from 1967, this circuit uses an unusual PUT today. The...