HP 37718A Installation And Verification Manual page 128

N OTE
Performance Tests
STM-0/STS-1 Transmitter Output Waveshape
and set to 1MΩ input impedance.
Load the Telecom Mask
4 On the oscilloscope, use the following key sequence to select and load
the required Telecom Mask:
a/ SHIFT (Blue Key) APPLICATION.
b/
TELECOM MASK/MASK
c/ Use ENTRY/MEASURE control to select STS1_93 in the
highlighted MSK FILES window.
d/
LOAD SETUP 8 M1M2
Compare Pulse with Mask
5 On the oscilloscope, use the following key sequence to compare the
pulse with the mask:
a/ RECALL 8
b/ DEFINE MEAS
c/ softkey
COMPARE
d/ softkey
TEST ON
e/ softkey
M1M2
f/
AFTER FAIL CONTINUE
g/ RUN
6 The oscilloscope will automatically display and compare an isolated
positive pulse with the mask limits. A PASS message should appear on
the Oscilloscope.
It may be necessary to select
or to visibly fit the waveform to the mask by adjusting the
MASK ALIGN
oscilloscope vertical gain/position and horizontal delay to obtain a PASS
on the Mask.
7 Measure the peak pulse amplitude at the mid pulse-width using the
oscilloscope and verify that this is nominally 530 mV.
Negative Pulse
8 On the Oscilloscope, use the following key sequence to access the
inverted mask.
a/ SHIFT (Blue Key) DISK
b/ softkey
DIRECTORY
c/ Use ENTRY/MEASURE control to highlight INV_MASK
d/
CHANGE DIRECTORY
3-60
softkey.
softkey.
softkey
softkey and
MASK
softkey
MASK AUTO
/