TM 11-5840-360-14-1-1
3.8 OPERATING PROCEDURES
13. Rotate the TUNE control about its center to
produce maximum grass on the PPI screen and maximum
3.8.1 Energizing Procedures
brilliance on the TUNE indicator.
14. Observe the PPI screen for echoes. Identify a
The energizing procedures for Radar Sets
weak echo at mid-range (halfway between the center and
AN/SPS-64(V)1, (V)2, (V)3 and (V)4 are given at the
the outer edge). Stop the antenna to point at a weak
target by holding the ANTENNA switch in the OFF position
to aid in fine-tuning.
15. Fine adjust the TUNE control until the echo is
3.8.2 Control Adjustments
strongest. Release the ANTENNA switch to resume
rotation.
1. Turn the PNL LIGHTS control clockwise until
NOTE:
control panel illumination is visible (if ambient lighting is
at a low level).
With no antenna rotation, the dimming
2. Turn the BRG SCALE control clockwise to
feature will cause the sweep to dim,
illuminate the compass ring (s) at the edge of the PPI.
thus preventing CRT burn.
3. Turn the RANGE RINGS control clockwise to
illuminate the range rings on the PPI.
16. Readjust the TUNE, CONTRAST, and/or GAIN
controls for optimum target presentation on the PPI. With
4. Turn the RANGE SELECT switch to the 24 MILE
the CONTRAST control properly adjusted, the two-level
position.
video enhancement feature of the radar will easily
5. Turn the VRM handwheel one turn clockwise.
distinguish between weak echoes (low level of brightness)
and strong echoes (high level of brightness).
6. Adjust the VRM intensity control (inner knob)
until the variable range ring is visible. Adjust the VRM
17. Turn the RANGE SELECT switch to the 6-MILE
READOUT control (outer knob) so that the digital range
position.
indication display is visible in the window above the 0
18. Turn the ANTI-CLUTTER SEA control slowly
mark of the indicator.
clockwise until the sea return is reduced to a degree that
7. Check that rotation of the VRM handwheel
presents a good picture without loss of small echoes. It
expands or reduces the size of the variable range ring
may also be necessary to adjust overall gain slightly by
and changes the digital range readout. Check the
turning the GAIN control. Short range picture quality can
alignment between inner and outer markers and the
be further enhanced by adjusting the ANTI-CLUTTER
reading displayed on the MARK scale of the RANGE
RAIN control and the CONTRAST control.
SELECT knob.
19. Turn the RANGE SELECT switch to 1.5 MILE
8. Check the EBL function by turning the EBL DIM
position.
control (inner knob) clockwise until the EBL is visible.
20. Turn the ANTI-CLUTTER SEA control slowly
Turn the EBL control to check that the position of the
clockwise. Sea return clutter will gradually decrease.
EBL display on the PPI changes.
Continue turning the control until close in echoes can be
9. Set the OFFSET switch down (toward operator).
distinguished. The ideal setting of the control depends
The PPI presentation will be offset toward the lower edge
largely on weather and sea conditions.
of the PPI screen by 70% of the CRT radius.
21. Adjust the RANGE RINGS control so that the
10. Turn the EBL READ switch (outer knob)
brightness of the rings is approximately the same as that
clockwise and observe that the EBL origin moves up to
of weaker echoes.
the center of the PPI screen. Release the EBL READ
22. Turn the RANGE SELECT switch to each of the
switch and observe that the EBL moves back down.
remaining ranges and note that the range rings appear
11. Set the OFFSET switch up and observe that the
with each selection. Observe that the corresponding
entire PPI presentation (rotating heading line flashing at
range lamp is illuminated at the top of the PPI display.
0 and EBL) moves back up to the center of the PPI
,
Also check for presence of the ship's heading flash on all
screen.
ranges. Hold the FTE ON/ FLASH OFF switch in the
FLASH OFF position and check that the heading flash
12. Turn the GAIN control fully clockwise. Turn the
does not appear on subsequent rotations. Release the
CONTRAST control clockwise until noise and echo
switch.
returns are visible on the PPI screen. Turn the GAIN
control counterclockwise until the gain is at the threshold
23. Turn the RANGE SELECT switch to the 3 MILE
where grass just starts to appear.
position.
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