HP 8340B Manual page 63

4-12.
PULSE MODULATION RISE AND FALL TIME (Cont'd)
Figure 4-14.
Pulse Modulation Rise Time Waveform
6.
The 90%
point of the
envelope
rise time should be less than 25 nanoseconds (5 horizontal
divi¬
sions) from the 10%
point.
7.
Adjust the oscilloscope horizontal position control to
view the modulation envelope
fall
time.
Position
the waveform
so
that the modulation envelope crosses the
90%
graticule at
a
vertical
graticule line similar to Figure 4-15.
Figure 4-15.
Pulse Modulation
Fall Time Waveform
8.
The
10%
point should be
<25
nanoseconds (5 divisions)
from
the
90%
point.
9.
Repeat
steps
5
through
8
at
CW frequencies of
3,
9,15, and,
if
the DUT
is
an HP
8340B,
22
GHz.
Set
the LO CW frequency to be 50
MHz
below the
DUT's
frequency.
HP 8340B/41B
Performance Tests