It is about the capacitor holding a charge still, yes, and it is also about the reference.I understand for the most part. Only thing I'm struggling with is that the AC/audio signal I am referring to is first being amplified by a transistor in a circuit powered by a 6V battery. Thus the transistor output swings as high as 6V and no lower than 0V. Then the signal is AC coupled by a series capacitor and input to a clamping circuit. The signal at this point (cathode of clamping diode) drops as low as -0.7V referenced to circuit ground. My question is how can I read a negative voltage across a circuit element when 0V is the lowest potential in the circuit? Is it simply because the capacitor is holding a charge from the previous positive cycle and therefore on the negative cycle, the diode is forward biased? In other words, my negative voltage reading is relative.
by Jake Hertz
by Aaron Carman
by Jeff Child
by Jake Hertz