HP 3336A - Page 120

Model
3336A/B/C
Performance
Tests
4-33. Phase Modulation Linearity.
4-34.
This
performance
test
verifies
that
the
-hp-
Model
3336
meets
the
Phase
Modulation
Linearity
specification
in
Table
4-1.
Specification:
The
phase
shift
of
the
main
signal,
caused
by
the
phase
modulation
input
voltage,
will
be
linear
within
.5%
of
the
peak
to
peak
phase
deviation,
compared
to
a
best
fit
straight
line.
Required Equipment:
dc
Power
Supply
-hp-
Model
6216A
dc
Voltmeter
-hp-
Model
3455A
Electronic
Counter
-hp-
Model
5328A
75
ohm
Feedthru
Termination
-hp-
Model
11094B
a. Connect the equipment as shown in Figure 4-12.
b. Set the 3336 controls as follows:
FREQUENCY oss tocsscwuewedeases ebatiud bet vaawieed 1 MHz
OUTPUT iicaaturvas eet mie tales Se srek ant ind hawt 75 ohm
AMPLITUDE osicsc es tate% ee casas ee ew bh elias +7.00 dBm
PHASE MODULATION............ 20.0... cece cece ON
c.
Set
the
electronic
counter
controls
to
measure
the
average
time
interval
between
input
A
and
input
B
(T.I.
AVG
A—B).
Set
the
number
of
intervals
averaged
to
10°.
d.
Set
the
power
supply
voltage
to
—
5.000
V,
+
.002
V.
Use
the
dc
voltmeter
to
adjust
this
voltage
as
precisely
as
possible.
This
is
the
first
voltage
(x9)
from
the
following
list:
x0
=
—5.000
V
x3
=
—2.000
V
x6
=
1.000
V
x9
=
4.000
V
x1
=
—4.000
V
x4
=
—1.000
V
x7
=
2.000
V
X10
=
5.000
V-
x2
=
—3.000
V
x5
=
0.000
V
x6
=
3.000
V
It
may
be
easier
to
obtain
an
accurate
0.000
V
by
disconnecting
the
power
supply
and
placing
a
short
across
the
3336’s
Phase
Modulation
input.
e.
With
the
RPG,
modify
the
phase
of
the
3336’s
main
output
until
the
electronic
counter
measures
a
time
interval
of
200
ns
+
.5
ns.
To
achieve
this
accuracy,
the
final
phase
in-
crements
must
be
in
.1°
steps.
f.
Without
changing
any
other
controls,
set
the
dc
power
supply
to
the
next
voltage
from
the
list
in
Step
d.
The
voltages
listed
in
Step
d
must
be
used
in
sequence
and
must
be accurate
to
within
.002
V.
g.
Record
the
time
interval
(Tp)
in
column
‘‘T’’
of
the
work
sheet
at
the
end
of
this
pro-
cedure.
4-35