The many changes to this radar set have improved
its minimum range capability, as well as made it more
reliable and easier to maintain.
General Theory of Operation
The AN/SPS-40 radar set, with the automation
module, is better able to detect targets over land and
water and to generate clutter-free target data. It has a
two-speed drive motor, which increases the antenna rate
to 15 rpm for high-data rate capabilities and operates at
a normal 7.5 rpm speed in the long-range mode (LRM).
Some special operating features of the
AN/SPS-40B/C/D/E include the following:
Long-range, long-range/chaff, and short-range
Automatic target detection (ATD)
Built-in-test (BIT) equipment
Four-pulse staggered pulse repetition frequency
Operator selectable antenna scan rate
Sensitivity time control (STC)
Figure 2-6 illustrates the AN/SPS-40B/C/D
DMTI/RVC radar system. The DMTI field change
replaces the analog moving target indicator with more
reliable and more easily maintained digital circuitry. It
also provides a new radar set control (RSC) and replaces
the duplexer with a solid-state unit. The RVC field
change allows the radar to interface with the AN/SYS-1
Installation of the solid-state transmitter, field
change (FC-11 ), replaces 11 shipboard units (units 2, 3,
4, 6, 16, 17, 18, 19, 21, 23, and 25) with five units (units
28 through 32) as shown in figure 2-7.
SIGNIFICANT FIELD CHANGES. As we
mentioned before, this radar set has had many changes.
Some of the more significant field changes are:
Radar video converter (RVC)interface with
Solid-state transmitter (SSTX)changes the
number of units in the configuration and the
nomenclature of the system
AN/SPS-40E Field Change 2changes the
two-cabinet PA configuration to a single cabinet
AN/SPS-40E Field Change 3replaces the
DMTI with a new coherent receiver processor
SIGNIFICANT INTERFACES. The An/SPS-
40B/C/D/E interfaces with shipboard display systems
via conventional radar switchboards and NTDS
switchboards. The AN/SPS-40B/C/D/E radar with
DMTI/RVC interfaces with the AN/SYS-1 Integrated
Automatic Detection and Tracking System (IADT).
FOR THE MAINTAINER. The increased use of
solid-state design and modular construction in the
AN/SPS-40 radar results in a longer mean time between
failures (MTBF) and a shorter mean time to repair
(MTTR). The new receiver and mti both use
built-in-test equipment to help in alignment and
The AN/SPS-40B/C/D/E radar is designed for
continuous operation during deployment. The
maintenance responsibilities are assigned to the ET
rating (NEC ET-1516, ET-1508 (with DMTI), and
ET-1511 (with FC-11)). The SPS-40s modular design
minimizes maintenance actions at the organizational
Organizational maintenance includes preventive
and corrective maintenance.
PM is performed
according to technical manuals and maintenance
requirement cards (MRCs).
CM is performed according to the corrective
maintenance section of the technical manuals and by the
Source Maintainability and Recovery (SM&R) code
assigned in the APL. You may be required to perform
any of the following actions:
Remove and replace cabinet-mounted piece
parts, modules, assemblies or sub-assemblies.
Repair modules, assemblies, or sub-assemblies
designated as shipboard repairable.
Turn in depot repairable items using prescribed