This circuit is from the 1992 Radio Electronics Handbook. The components used are from the period, with emphasis on the 2-digit display driver.
This stage of IF to 455 kHz operates with voltages from 1.5 V. We find it in a 90s Popular...
This trigger circuit with transistors, which may be 2N2222, was found in a 1967 publication. The...
We found this thyristor power supply in a 1987 documentation. It uses common SCRs as rectifiers and...