FFT Analyzer Basic FAQ

Like a regular oscilloscope, an FFT analyzer allows you to select between two input coupling options: AC coupling and DC coupling. DC coupling allows the input signal to pass through unchanged, while AC coupling cuts off the DC component before passing through. The signal is then fed into an input attenuator and amplifier.

The main uses of these two types of bonding are as follows:

 

[AC coupling]

• When you want to accurately measure the AC component of a signal that contains a DC component.
• When you want to measure the overall value (effective value) of only the AC component.
• Conventional acoustic vibration measurement
• When using a CCLD sensor

 

[DC coupling]

• When you want to measure including the DC (direct current) component
• When you want to accurately measure AC components at low frequencies (below 1 Hz)