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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 C W
FREQ Control
to 300 MHz
OUTPUT Control
to +10dBm
ALC Switch
t o 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 + l W B m . Turn the Front
Panel vernier OUTPUT control t o -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
t o n f
CENTER FREQUENCY Control
to 250 MHz
SWEEP WIDTH Control
to 520 MHz
OUTPUT Control
to +10dBm
SWEEP TIME Switch
t o .l-.O1 sec
Four Paddle Switches
down
50 har marker Switch
on
MARKER WIDTH Switch
to WIDE
MARKER SIZE
for a display
similar t o 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 t o 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, t o 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, a s 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 a s 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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