shortcomings must be recorded in accordance with the requirements of TM 38-750. If a
deficiency cannot be remedied by the organizational repairman, higher category maintenance or
repair is required. Perform the 11 following checks and services in the sequence given.
(1) The first item in the quarterly check is completeness of equipment. This is the
same check that was made in an operator's daily PM. This check insures that the equipment is
complete. A complete list of items comprising Radio Set AN/GRC-103 is contained in TM 11-
5820-540-12 paragraph 1-6. This list contains transmitter and receiver components, antenna
system components, cables, tools, and running spares.
(2) The second check involves equipment installation. This is an inspection of the
antenna system to insure that it's installed in the manner specified in Lesson 1. Also check that
the interunit connections are tight and connected in the proper manner.
(3) Cleanliness is the next quarterly PM check. The equipment should be cleaned and
the air filter changed. Cleaning of the equipment and air filter are accomplished in the same
manner as specified in Item (2) of the daily inspection and Item (1) of the weekly PM. If
trichloroethane is used for cleaning DO NOT expose its fumes to an open flame or hot metal.
(4) The fourth check is for preservation. This involves checking all surfaces for
fungus, rust, and corrosion. A cloth dampened with trichloroethane may be used to remove any
fungus. Remove rust and corrosion from metal surfaces by lightly sanding with fine sandpaper.
Then brush two thin coats of paint on the bare metal to protect it from corrosion.
(5) The fifth check is to insure that all publications pertaining to the radio set are
complete, serviceable and current. DA Pamphlet 310-4 will provide a list of publications and the
latest changes available.
(6) Check to determine if any new Modification Work Orders (MWO) have been
published. All URGENT MWO's must be applied immediately, and all NORMAL MWO's must
be scheduled. DA Pamphlet 310-7 will provide this information.
(7) The seventh quarterly PM check is for noisy operation of the centrifugal fan. The
fan is located in the transmitter case in the RF head compartment. The organizational repairman
is not authorized to replace the centrifugal fan. The radio set must be sent to a higher category of
maintenance when this defect is found. Fold-Out 13 shows the location of the fan.