Harris RF Communications’ products and systems are supported by up to four levels of maintenance. Each maintenance level relies on a defined set of support documentation and equipment in order to fulfill its maintenance tasks. The tasks performed at each level grow in complexity as the problem is narrowed to the component on the board. This concept assists the maintainer by supplying only the information and material required for that maintenance level. These levels may be combined to support any particular user maintenance philosophy. User maintenance philosophy will be incorporated into the appropriate training class. The operation and maintenance information presented will permit users to maintain their equipment to meet the highest specifications possible in an expeditious manner. Level I Level I maintenance is generally performed by the equipment operator. This maintenance is very limited and restricted to fault recognition and detection at the radio system level. Level II Level II maintenance is repair of the end item, that is the system, by removal and replacement of the Line Replaceable Unit (LRU). LRU is defined as whole units (receiver-transmitter, power amplifier, antenna coupler, etc.) and ancillary items (handsets for manpacks, cables, and antennas for manpacks). Level III Level III maintenance is defined as repair of the LRU by removal and replacement of modules and chassis–mounted components, all referred to as Shop Replaceable Units (SRUs). The unit maintenance manual, along with spares availability, tools, test equipment, and training will support this level of maintenance. At this level, the maintainer requires a higher level of training in the advanced use of Built-in Test (BIT), as well as manual troubleshooting maintenance procedures. Level IV Level IV maintenance is defined as repair of the SRU by removing and replacing defective piece part components on the individual circuit cards contained within the modules (SRU). Additionally, repairs may be performed by the replacement and discard of entire SRUs. This maintenance is normally performed at the Harris Depot. It is the most advanced level of maintenance and requires the most logistics support. Support documentation, specialized training, and a sophisticated complement of support equipment is required to perform depot maintenance. Pricing Each maintenance level is priced according to product and/or system complexity.