4-6. POWER SUPPLY
The 28 Vdc input is filtered and protected against transients, overvoltage, and reverse voltage. A pulse width
modulator regulates output voltage by varying the pulse width to the de/de converter. The de/de converter chops
the 28 V dc at a constant frequency. The square wave produced is then rectified and filtered to the correct dc
The series regulators charge the regulated black dc voltages into lower dc voltages. The shunt regulators provide
a constant current to the red outputs. In addition, they regulate to a lower dc voltage.
The PT/CT OUT is a pull-up voltage to the PT/CT OUT from the bit sync module.
Figure 4-1. Power Supply Functional Block Diagram
Section Il. REPAIR PARTS, SPECIAL TOOLS, TMDE, AND SUPPORT EQUIPMENT
COMMON TOOLS AND EQUIPMENT
For authorized common tools and equipment, refer to the Modified Table of Organization and Equipment (MTOE)
applicable to your unit, Common tools required for maintenance of the dra are listed in the Maintenance Alloca-
tion Chart. It is appendix B of TM 11-5821-333-12.
4-8. SPECIAL TOOLS, TMDE, AND SUPPORT EQUIPMENT
No special tools are required. For TMDE
appendix B of TM 115821-333-12.
and support equipment refer to the Maintenance Allocation Chart,