4-27. PRELIMINARY SERVICING AND ADJUSTMENT. (CONT)
AZIMUTH TILT BLANKING ALINEMENT (CONT)
Alternately place ANGLE VOLTS switch in EL and OPERATE positions. Adjust R37 AZ WIDTH control so top of
blanked range mark section coincides with 1.5-degree artificial sweep trace.
Place SCAN switch on master pulse generator to OFF position.
Remove clinometer from elevation antenna clinometer mount and store in receiver door.
ELEVATION SERVO BLANKING ALINEMENT
A 3-degree section of range marks on azimuth display is blanked to indicate servo position of elevation antenna during
the precision mode of operation. This blanked section must be properly oriented on azimuth display in order for elevation
antenna servo data to be accurate. The elevation servo blanking alinement requires two persons: one at radar site and
one at control-indicator site. Perform elevation servo blanking alinement as follows.
Elevation servo blanking alinement procedure must be performed for each control- indicator.
Unless otherwise indicated, perform the following steps only on control-indicator on which
elevation servo blanking alinement is being performed.
Ensure all controls and switches are in positions indicated in Preliminary Operating Procedure (para 2-5).
On pulse generator, place RANGE MILES switch to position 40.
Use ANTENNA control on master control-indicator to servo elevation antenna to zero degrees as indicated on
At radar site, manually rotate azimuth antenna to a scan angle of zero degrees as indicated on elevation
protractor on azimuth antenna drive.
Alternately place ANGLE VOLTS switch on pulse generator in AZ and OPERATE positions. Adjust ART ANGLE
V control so artificial sweep trace coincides with operate sweep on azimuth display. Record ART ANGLE V
control dial indication.
Place SCAN switch on master pulse generator to ON position.
To prevent being hit by scanning antennas, ensure personnel are clear of antenna scan area
before performing step 7.
Set ART ANGLE V control dial to indicate 15 divisions more than indication recorded in step 5.
ART ANGLE V control dial is now set to produce a 1.5-degree artificial sweep trace.
Alternately place ANGLE VOLTS switch in AZ and OPERATE positions. Adjust R22 EL SERVO POS control on
AZ-EL blanking pulse generator cards so top edge of blanked range mark section coincides with 1.5-degree
artificial sweep trace.