I didn't monitor my novice keying, because the taping of the key made the 
sx71 bounce around.  I finally had to put it on it's own table.  I could 
hear the power supply hum in the globe chief, and later the valiant, but a 
side tone only became necessary when I got a paddle and keyer.  I tried to 
learn a bug for a year, never got the hang of it.