MAINTENANCE
Model
2001
5.5.9 LEVEL MIN AND MAX ADJUSTMENT
-
MODULE MlOH
Preset the Front Panel controls as follows:
BAND Switch to 1
MODE Switch to CW
FREQ Control to 300 MHz
OUTPUT Control to
+10dBm
ALC Switch to INT
Set the power meter to read +10dBm and connect the
thermistor mount to the sweep generator's RF output con-
nector. Adjust the
MlOH LEVEL MAX control to produce
a power meter reading of exactly
+lWBm. Turn the Front
Panel vernier OUTPUT control to
-10dBm (completely
counterclockwise), change the power meter scale to read
-10dBm and adjust the MlOH LEVEL MIN control to pro-
duce a power meter reading of exactly
-10dBm. Some
interaction exists between the LEVEL MIN and LEVEL
MAX controls so repeat the adjustment until both the +10
and -1
0dBm readings are obtained.
5.5.10 CENTER FREQUENCY AND SWEEP WIDTH
ADJUST
-
Bands 1. 2 and 3
Connect SWEEP, SCOPE and RF DET as shown in TYPI-
CAL SET-UP, Figure
5-4. Set:
BAND Switch to 1
MODE
SwiTch to nf
CENTER FREQUENCY Control to 250 MHz
SWEEP WIDTH Control to 520 MHz
OUTPUT Control to
+10dBm
SWEEP TIME Switch to .l-.O1 sec
Four Paddle Switches down
50 har marker Switch on
MARKER WIDTH Switch to WIDE
MARKER
SIZE for a display
similar to Fig-
ure
5-5.
The sweep generator should be thoroughly stabilized by
operating approximately one hour with all covers in place
before the following adjustments are made.
Adjust the scope per
Figure'5-5. Adjust the M9H CENT
control, band 1, to position the 250 MHz marker at the
exact center of the scope display. Adjust the M2H SWEEP
WIDTH 1 to position the
0 frequency and 500 MHz mark-
ersas shown in Figure 5-5. Compromise between 0 and 500
if necessary.
Set BAND switch to
2,
wait
5
minutes, then adjust the
M19H CENT, BAND 2, to position the 700 MHz marker to
the exact center of the display. Adjust the M2H SWEEP
WIDTH 2, to position the 450 and 950 MHz markers as
shown in Figure
5-5. Compromise between 450 and 950 if
needed.
Set band switch to 3, wait 5 minutes, then adjust the
M19H
CENT, BAND 3 to position the 1150 MHz marker to the
exact center of the display. Adjust the M2H SWEEP
WIDTH, BAND 3, to position the 900 and 1400 MHz
markers as shown in Figure
5-5. Compromise between
900 and 1400 if needed.
5.5.1 1 FINAL ADJUSTMENT OF
M1H CLAMP
While operating the sweep generator as
set
up in paragraph
5.5.10, carefully note the extreme left side of the scope dis-
play. The trace should extend
0.2cm beyond the first
graticule line, as shown in Figure
5-5.
Switch SWEEP TlME from .I-.O1 sec to LINE, and adjust
the
M1H CLAMP for the identical display width.
5.5.12 SWEEP SAMPLE ADJUSTMENT M5H
Connect the RF detector to the SWEEP SAMPLE OUT Jack
of the M5H module, using the adapter cable supplied in
the service kit, and adjust the M5H SWEEP SAMPLE ADJ.
to produce a detected output of 35 millivolts when the
Front Panel BAND switch is set to band 1.
5.5.13 MARKER SlZE ADJUSTMENT
Each marker module has a SlZE adjustment potentiometer
which is accessible from the under side of the sweep genera-
tor, when the bottom cover is removed. (See Figure
5-2).
The control is adjusted until a saturated marker is obtained
on the scope display when operating the unit as shown in
the typical set-up. Figure
5-4. A saturated marker is ob-
tained when a further increase in the marker modules SlZE
adjustment does not increase the marker amplitude on the
scope display. Increasing the size adjustment beyond this
point will result in spurious markers on the display.
5.6
TROUBLESHOOTING
Trouble shooting is generally a systematic procedure of
"divide and conquer." A thorough understanding of the
block diagram and circuit description located in Section 4
of this manual will enable the trouble symptom to be
associated with a particular module. Once this has been
accomplished the module can be replaced or trouble shot
with the aid of the module schematic. A problem in a
power supply often causes many
symptoms pointing to
MAINTENANCE
5.5.9
LEVEL
MIN
AND
MAX
ADJUSTMENT
-
MODULE
M10H
Preset the
Front
Panel
controls
as
follows:
BAND
Switch
MODE
Switch
F R EQ
Control
OUTPUT
Control
ALC
Switch
to
1
to
CW
to
300
MHz
to
+10dBm
to
INT
Set
the
power
meter
to
read
+lOdBm
and
connect
the
thermistor
mount
to
the
sweep generator's RF
output
con-
nector.
Adjust
the
MlOH
LEVEL
MAX
control
to
produce
a
power
meter
reading
of
exactly
+lOdBm.
Turn
the
Front
Panel vernier
OUTPUT
control
to
-lOdBm
(completely
counterclockwise),
change the
power
meter
scale
to
read
-lOdBm
and
adjust
the
MlOH
LEVEL
MIN
control
to
pro-
duce a
power
meter
reading
of
exactly
-lOdBm.
Some
interaction
exists between the
LEVEL
MIN
and
LEVEL
MAX
controls
so
repeat
the
adjustment
until
both
the
+10
and
-lOdBm
readings are obtained.
5.5.10
CENTER
FREQUENCY
AND
SWEEP
WIDTH
ADJUST
- Bands
1,
2 and 3
Connect
SWEEP, SCOPE and RF
DET
as
shown in
TYPI-
CAL
SET-UP, Figure 5-4. Set:
BAND
Switch
MODE
Swi~ch
CENTER
FREQUENCY
Control
SWEEP
WIDTH
Control
OUTPUT
Control
SWEEP
TIME
Switch
Four
Paddle Switches
50
har
marker
Switch
MARKER
WIDTH
Switch
MARKER
SIZE
to
1
to
Af
to
250
MHz
to
520
MHz
to
+lOdBm
to
.1-.01
sec
down
on
to
WIDE
for
a display
similar
to
Fig-
ure 5-5.
The
sweep generator should
be
thoroughly
stabilized
by
operating
approximately
one
hour
with
all covers in place
before
the
following
adjustments are made.
Adjust
the scope per Figure '5-5.
Adjust
the
M9H
CENT
control,
band
1,
to
position
the
250
MHz
marker
at
the
exact center
of
the scope display.
Adjust
the
M2H
SWEEP
WIDTH
1
to
position
the
0
frequency
and
500
MHz
mark-
ers
as
shown in Figure 5-5.
Compromise
between 0 and
500
if
necessary.
Set
BAND
switch
to
2,
wait
5
minutes,
then adjust the
M19H
CENT,
BAND
2,
to
position
the
700
MHz
marker
to
5-12
Model 2001
the
exact
center
of
the display.
Adjust
the
M2H
SWEEP
WI
DTH
2,
to
position
the
450
and
950
MHz
markers
as
shown in Figure 5-5.
Compromise
between
450
and
950
if
needed.
Set band
switch
to
3,
wait
5
minutes,
then adjust the M 19H
CENT,
BAND
3
to
position
the
1150
MHz
marker
to
the
exact center
of
the display.
Adjust
the
M2H
SWEEP
WIDTH,
BAND
3,
to
position
the
900
and
1400
MHz
markers
as
shown in Figure 5-5.
Compromise
between
900
and
1400
if
needed.
5.5.11
FINAL
ADJUSTMENT
OF
M1H
CLAMP
While
operating
the sweep generator
as
set
up
in
paragraph
5.5.10,
carefully
note
the
extreme
left
side
of
the scope dis-
play. The trace should
extend
0.2cm
beyond
the
first
graticule line,
as
shown in Figure 5-5.
Switch
SWEEP
TIME
from
.1-.01
sec
to
LINE,
and adjust
the M
1H
CLAMP
for
the identical display
width.
5.5.12 SWEEP
SAMPLE
ADJUSTMENT
M5H
Connect
the RF
detector
to
the SWEEP
SAMPLE
OUT
Jack
of
the
M5H
module,
using the adapter cable supplied in
the
service
kit,
and adjust the
M5H
SWEEP
SAMPLE
ADJ.
to
produce a detected
output
of
35
millivolts
when
the
Front
Panel
BAND
switch
is
set
to
band
1.
5.5.13
MARKER
SIZE
ADJUSTMENT
Each
marker
module
has a
SIZE
adjustment
potentiometer
which
is
accessible
from
the
under
side
of
the sweep genera-
tor,
when
the
bottom
cover
is
removed.
(See
Figure 5-2).
The
control
is
adjusted
until
a saturated
marker
is
obtained
on the scope display
when
operating the
unit
as
shown in
the
typical
set-up. Figure 5-4. A saturated
marker
is
ob-
tained when a
further
increase in the
marker
modules
SI
ZE
adjustment
does
not
increase the
marker
amplitude
on
the
scope display. Increasing the size
adjustment
beyond
this
point
will
result in spurious markers
on
the display.
5,6 TROUBLESHOOTING
Trouble
shooting
is
generally a systematic procedure
of
"divide
and
conquer."
A
thorough
understanding
of
the
block
diagram and
circuit
description
located
in
Section
4
of
this
manual
will
enable the
trouble
symptom
to
be
associated
with
a
particular
module.
Once
this
has
been
accomplished the
module
can be replaced
or
trouble
shot
with
the aid
of
the
module
schematic. A
problem
in a
power
supply
often
causes
many
symptoms
pointing
to
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