Fluke 6060B - Synthesizer PCA Adjustments

MAINTENANCE
CALIBRATION
ADJUSTMENTS
The
following
only need
adjustment
if the
associated
circuits are
repaired.
3. L49
20-kHz Notch Filter
Adjustment
L50 40-kHz
Notch Filter
Adjustment
4. R 104 VCO
Upper Clamp
Adjustment
5. C206
SOO-MHz
Oscillator
Adjustment
6. C240
10-MHz
Lock-Range
Centering
adjustment
Each of
the
following
adjustment
procedures
is
independent;
that is,
they can
be
done
individually
or in any
sequence.
Figure 4C-3
shows the
top
view of
the
module
plate.
1.
Reference
Frequency
Adjustment, R230
TEST
EQUIPMENT
Frequency
Standard
Oscilloscope
REMARKS
The accuracy
of
this
adjustment
depends on
that
of the
frequency
standard.
The Signal
Generator may
be
equipped
with either
Option
-130
High-Stability
Reference, or
Option
-132 Medium-Stability
Reference.
The
frequency
reference
operation and
adjustment
procedure
depend on this
configuration.
That
is,
the
instrument
reference may
be the
10-MHz crystal
oscillator,
the
High-Stability
Ref-
erence,
the
Medium-Stability
Reference
or an
external signal.
Skip this
procedure if
the
UUT is
equipped with
the
High-Stability
Reference,
or
Medium-Stability
Reference and
use
the
adjustment
procedures
in
Section 6 of
this
manual. Also
perform the
Sub-Harmonic
Reference
Adjustment
described
on
page
4C-15 of this
manual.
PROCEDURE
The
UUT
reference
waveform is
viewed
on
the
Oscilloscope
while
triggering
on the
Frequency
Standard.
The
10-MHz
adjustment, R230,
is
adjusted
for a
stationary
display.
a.
Remove the
instrument top
cover and the
10-MHz
adjustment R230
access
screw from
the module
plate cover.
b.
Connect the UUT
rear panel 10
MHz OUT
to the
Oscilloscope
vertical
input.
c.
Connect the
Frequency
Standard
output to
the
Oscilloscope
external
trigger
input.
d.
Set the
UUT
rear panel
REF INT/ EXT
switch to INT,
and set
the vertical
controls of the
Oscilloscope
to
display the
UUT
10-MHz signal,
e. Set
the
Oscilloscope
for external
triggering, and
adjust the
timebase
for 0.
1
us/div.
f. Adjust R230
for a drift of less
than one
cycle per
second.
4C-11