94951
The importance of loop gain as a parameter for characterizing electronic feedback amplifiers was first recognized by Heinrich Barkhausen in 1921 , and was developed further by Hendrik Wade Bode and Harry Nyquist at Bell Labs in the 1930 s .
 Heinrich Barkhausen, Hendrik Wade Bode, Harry Nyquist, Bell Labs
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 Heinrich Barkhausen, Hendrik Wade Bode, Harry Nyquist, Bell Labs