LeCroy 9450 - Page 28

Switch
between 50
S DC
and GND,
and 1 MS
DC and GND.
Check:
-
the trace
should
not
move
more than
a
minor division
or 1 mV
Repeat
the same test
for
CH2.
5
Input Impedance
Set
the DSO
CHI input
to
1 MS
DC with any time
base
and
gain.
Check
with an
ohmmeter:
-
input
impedance must
be
1 MS
±
2
%
Set
DSO
CHI input
to
50
S,
20 mV/div
with any time
base.
Check:
-
input
impedance must be 50 S
±
2%
Repeat
50
S
test
for
50, 100,
200,
500 and 1000 mV/div.
Repeat all
impedance checks for CH2.
6
Front-End
Set
the
DSO
as
follows:
-
turn on
the trace
for
CHI
-
Grid
normal
-
Input
50
S, gain 100 mV/div,
offset zero
-
Trigger:
SMART
(COMPLEX) Trigger:
OFF
Source:
CHI
Coupling: DC
Mode:
NORM
Delay:
50%
Level:
zero
-
Time/div
=
.1
psec/div
-
BWL OFF
Apply
a
600
mV peak-to-peak
1 MHz
square
wave from
a
fast (less than
1
nsec)
risetime
function generator (for example
TEK PG502)
to
CHI input.
Press
the
Interleaved Sampling
button
on the oscilloscope to
turn on
the RIS
mode.
3