Indicated for stereophonic sound applications, this circuit was found in the April 1983 issue of Radio Electronics magazine. The indicated circuit is the NE570, launched at the time.
Today we have more compact solutions. This is from a Radio Electronics magazine from October 1990....
This filter was found in Texas Instruments documentation from the 1980s. The circuit uses a common...
16 commercial test circuit for tubes and transistors appeared in Radio Electronics magazine in...