Agilent Technologies 53220A, User Manual, Page: 132 / 294

132 53220A/53230A User’s Guide
4 53220A/53230A Input Signal Conditioning
INPut[{1|2}]:LEVel[{1|2}]:RELative {<percent>|MINimum|MAX-
imum|DEFault}
INPut[{1|2}]:LEVel[{1|2}]:RELative? [{MINimum|MAXimum|
DEFault}]
(query form)
Threshold values are from 10% to 90% with 5% resolution. In order to specify
a relative threshold level, auto-level must be enabled .
LEVel
/
LEVel1
sets the relative threshold for all measurements except
rise/fall time and single-channel time interval. For rise/fall time measure-
ments,
LEVel
/
LEVel1
sets the lower reference and
LEVel2
sets the upper
reference. For single-channel time interval,
LEVel
/
LEVel1
sets the relative
threshold for the start event and
LEVel2
sets the threshold for the stop event.
CONFigure
and
MEASure
set the threshold to 50% and enable auto-leveling .
A reset (
*RST
) or front panel preset (
Preset
) also sets the threshold to 50% and
enables auto-leveling.
Relative Threshold Example
//set a relative trigger threshold
CONF:FREQ 1E6, 0.1, (@1) // measure 1 MHz signal
INP:IMP 50 // set impedance 50 ohms
INP:RANG 5 // set range to 5V
INP:COUP AC // set AC coupling
INP:LEV:REL 30 // threshold level at 30%
Measuring Low Frequency Signals
For all counter functions, auto-level should not be used for frequencies
< 50 Hz. Threshold levels should be set using absolute values (see “Specifying
an Absolute Threshold Level”) .
The
MEASure
command should not be used with frequencies less than 50 Hz
as the command configures the counter (including enabling auto-level) and
makes an immediate measurement.