HP 3562A Service Manual page 433

FAULT ISOLATION
I N 8 T L I N
:1 . 5
d B
P e a k
V
- :1 .
F x d
I N 8 T L I N
:1 . 5
d B
P e a k
V
- :1 . 5
F x d
Figure 7- 1 5 Calibration Curves
Calibration FCiilures
There are three type of calibration failures: calibration wait, cal . i bration accuracy, and
calibration source. Calibration failure messages are entered in the test log on power-up
and when self-test or TEST ALL are run. A calibration wait failure means the calibration
measurement did not complete within the specified time. A calibration accuracy failure
means the magnitude or phase values exceeded the following calibration limits:
Single Channel Flatness
± 1 .5 dBVpk,
± 3.0 dBVpk, ±400
Single Channel Phase at 0°
±1.5°
If the calibration accuracy failure occurs, the failure is entered in the test log and the
calibration curves are used in measurement reading. Any assembly in the instrument can
cause a calibration failure. If calibration fails, run the TEST ALL diagnostic to isolate the
failing assembly (refer to 7-7). It is also possible that all the assemblies pass their self­
tests and there still i s a calibration failure.
If the assemblies self-tests pass but there is a 'Calibration Wai t ' failure, the measurement
may not be triggering. Veri f y the trigger circuits in the instrument (go to 7-11).
8 :1 Un c a l
5
Y 0
8 :1 U n c a l
Y 0
U n i f
H z
U n i f
H z
MODEL 3562A
O v :1
:1 0 0 k
O v :1
:1 0 0 k
7-69