Radar trigger(s)
Radar antenna azimuth (stabilized and
unstabilized)
Dead reckoning information
Ship’s heading
Radar set sensor ID
The SDC also contains the necessary circuitry for
future growth and expanded use in data distribution. A
compatible switchboard is required to interface the data
from various radar sets with other systems.
SB-4229/SP Switchboard
The SB-4229/SP switchboard, shown in figure
2-14, replaces all SB-440, SB-1109, and SB-1505
switchboards. It provides selectable distribution of data
from any Navy conventional search radar set. The
CPU-controlled switchboard can accept signals from 16
radar sets and five IFF interrogator sets, then distribute
them to nine individual radar indicators and nine IFF
decoders. It can also accept mode control from any IFF
decoder associated with any of the radar indicators and
switch the mode control of the IFF interrogator
associated with the radar set being viewed on that
indicator. This process is explained in more detail in
chapter 3.
The SB-4229/SP switchboard allows radar and IFF
signals from ship’s radar and RADDS data stream inputs
to be selected from up to 16 signal data converters. It
provides up to nine selectable outputs to the AN/SPA
series radar indicators. So, up to nine different operators
can select one of 16 input sensors to display at their
indicator. Each of the 16 input sensors can consist of
three radar videos, RADDS data stream, and IFF control
with its associated videos. The more significant design
features include:
Local or remote selection of input sensors
Conversion of RADDS data stream back to
analog (for older indicators)
Distribution of any of the 16 input sensors to any
of up to nine separate radar indicators
Detection of improper operation by self-test
(BIT)
Figure 2-14.—Radar Distribution switchboard, SB4229/SP.
Maintenance
The maintenance of the AN/SPA-25G, CV-3989/SP,
and the SB-4229/SP is performed by the Electronics
Technician (ET) assigned maintenance responsibilities
for the surface search radar or conventional radar
display and distribution systems.
Organizational maintenance consists of corrective
and preventive maintenance actions. Preventive
maintenance is performed according to the maintenance
requirement cards (MRCs).
Shipboard personnel perform corrective
maintenance according to the corrective maintenance
sections of the applicable technical manuals and as
reflected by the maintenance code assigned in the
equipment APL.
CM may require (1) removal or
replacement of cabinet mounted piece parts, (2)
2-22
