HP 37718A Installation And Verification Manual page 113

N OT E
Performance Tests
External Mux/Demux
DS-1 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
Load the Telecom Mask
9 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 DS1_NEW in the
highlighted MSK FILES window.
d/
LOAD SETUP 8 M1M2
Compare Pulse with Mask
10 On the oscilloscope, use the following key sequence to compare the
pulse with the mask:
a/ RECALL 8, (Ensure CH1 Impedance is reset to 1M
TRIGGER,
to ).
Trig'd
b/ DEFINE MEAS
c/ softkey
COMPARE
d/ softkey
TEST ON
e/ softkey
M1M2
f/
AFTER FAIL CONTINUE
g/ RUN
Using the balanced to unbalanced converter reduces the pulse amplitude
by a factor of 1.266. This will cause the comparison with the mask to fail.
To overcome this select CHAN 1 ON and reduce the Volts/Division setting
(highlighted on the softkey display). Reduced Volts/Division = highlighted
value/1.266. The new value can be entered using the keypad
11 The oscilloscope will compare the negative pulse with the mask limits.
A PASS message should appear on the Oscilloscope.
softkey
softkey.
softkey.
SETUP and set
PATTERN TRIGGER
softkey
Ω
. Select
softkey
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