HP 8901B Operation And Calibration Manual page 114

4-6 Help
Decrease level
of input signal.
Increase level
of input signal.
Same Error
Ensure that the level
of the input signal
remains stable.
Increase RF
input attenuation.
Decrease selected
RF input attenuation.
If
Range Hold
is being used,
check ranae limits.
No Error
New Error
Remember
If
the error or reading remains the same after the AUTOMATIC OPERA-
TION
key
has been pressed, the error is being caused by an
input
problem.
Look
up
the error code in Table 4-2 and take the action recommended for
"Input Problem".
I f
the error goes away after the AUTOMATIC OPERATION key has
been pressed, the error was caused
by
an operating problem. Look
up
the error code
in Table 4-2 and take the action recommended for
"Operating Problem".
I f the error is replaced by a different error or dash code after the AUTO-
MATIC OPERATION
key
has been pressed, the original
error
was being
caused
by
a combined
input
problem and operating problem. Look
up
the
error code displayed
by
the instrument
after
the AUTOMATIC OPERATION
key
was pressed. Take the action recommended for
"Input
Problem".
Because of the wide variety of input signals and the operating
flexibility of the HP 8901B, i t is not possible to list all
recovery actions for each error code. After using the table to
determine the cause of the problem, you may discover other
recovery procedures that are better suited to your application.
Table
4-3.
RF
Power and
TRFL
Error Codes (1 of
3)
Problem Description
Display
Code
Questionable
Measuremeni
r
1.
Measurement is very inaccurate
2. Measurement is slightly inaccurate.
Instrument is unable to find an input signal.
Instrument has detected an input signal
and is attempting to set up measurement.
Continuous display indicates instrument
is having difficulty tuning to input signal
IF signal within IF passband but not
centered well enough to guarantee
measurement accuracy (due to manual tuning).
Input circuits overdriven.
Input circuits underdriven.
Input Problem
___
1. Check tuning.
Refer
to
Tuni n g (4-2).
2. Check RF Power
calibration (4-2)
Set input signal
level to between
0 and -20 dBm,
and check tuning.
Refer to Tuning (4-2).
Manually tune
to input signal.
Operating Problem
Recheck operating
conditions being used.
Re-check operating
conditions being used.