This power supply was found in a RCA publication from the 1970s. The circuit uses transistors from that time. Modern equivalent transistors can be used.
Published in Popular Electronics with the curious name of Obnoxious Noisemaker, this 1968 circuit...
This preamplifier circuit for turntable cartridges was found in the March 1994 issue of...
E) This circuit was found in documentation from the 1980s. The integrated circuit used is not very...