Keysight 53210A, Руководство пользователя

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53210A Input Signal Conditioning 4
Keysight 53210A User’s Guide 109
Input Coupling
The input to the 53210A counter is either DC (direct) coupled or AC (capacitive)
coupled, and is set using the command:
INPut[1]:COUPling {AC|DC}
INPut[1]:COUPling? (query form)
AC
coupling removes the signal’s DC content and centers the signal at 0V. The
measurable frequency range (channels 1 and 2) with AC coupling is:
– AC = 10 Hz - 350 MHz
– DC = 1 mHz - 350 MHz
DC
coupling extends the frequency range across the full bandwidth of the
instrument (1 mHz - 350 MHz).
CONFigure
and
MEASure
do not change the
coupling setting. Following a reset (
*RST
) or front panel preset ( Preset ), the
coupling is set to
Α C
.
When selecting AC or DC coupling, the amplitude of the input signal must also be
considered. DC coupling is applicable for most measurements, especially those
requiring a specific trigger level. Rather than reducing the signal amplitude by
changing the counter range, AC coupling can be used to bring the signal in
contact with the hysteresis window defined by the trigger level. This is
represented in Figure 4-2 (also see “ Threshold Level and Sensitivity ”).
DC AC
10 Hz
1 mHz