This stage of IF to 455 kHz operates with voltages from 1.5 V. We find it in a 90s Popular Electronics. The integrated circuit is uncommon today.
This circuit uses unijunction transistors and drives a small speaker through an output...
This circuit, found in a publication from the 1980s, can have its output voltage determined by the...
The operational amplifier for this circuit, found in a 1979 publication, may be the 741....