Keysight 53210A - Noise Rejection (Hysteresis)

4 53210A Input Signal Conditioning
118 Keysight 53210A User’s Guide
A
frequency setting of 10 kHz decreases the auto-level period for all frequencies
>
10 kHz. A frequency setting of 50 Hz provides auto-leveling for frequencies
down to 50 Hz. The
frequency selected should be based on the lowest expected
frequency in the measurement.
The auto-level frequency is a system setting which applies to all counter
channels, and should be noted when making two-channel measurements.
The default setting is 50 Hz. The value is stored in non-volatile memory and does
not change when power is cycled or following a reset (
*RST) or a front panel preset
(Preset).
CONFigure and MEASure enable auto-level and set a relative threshold of
50%, but do not change the auto-level frequency.
System Auto-Level Range Example
CONF:FREQ 100E6, (@1) // measure 100 MHz signal
SYST:ALEV:FREQ 10.0E3 // set auto-level frequency
INP:IMP 50 // set impedance to 50 ohms
INP:RANG 5 // set range to 5V
INP:COUP AC // set AC coupling
INP:LEV:REL 65 // set 65% relative threshold
Noise Rejection (Hysteresis)
Threshold sensitivity (Figure 4-4) to the input signal is a function of the amount of
noise rejection or hysteresis. Noise rejection (the hysteresis band) at the counter
input is increased or decreased with the command:
INPut[1]:NREJection {OFF|ON}
INPut[1]:NREJection? (query form)