HP 8901B Operation And Calibration Manual page 313

Model
8901B
Operation
HP-IB PROGRAM CODES
The codes for performing the various limit operations are provided in "Procedures".
RATIO off
=
R O
RATIO
on =
R1
COMMENTS
Relative Limits Not Possible
The test for out-of-limit results is performed on the actual measurement results, not upon the displayed
number. Thus, if the Ratio feature is enabled simultaneously with the Limit feature, the limit test is
still based on the measurement result, not the computed ratio. Limits cannot be set in terms of relative
measurement results.
Importance of Key Sequence
If Special Function
14.1
or
14.2
is initiated with no previous numeric value, the ratio reference becomes
the entered value. The desired limit must be entered before the Special Function numeric code.
Limit
3-221