2-1 Procedures for Replacing Components
a. What you will need for this exercise is a complete AN/ASN-128, TK-
101/G with the ASN-128 set up on a bench position or installed in the
aircraft. Each procedure is outlined in TM 11-5841-281-12.
b. After each minor (lamps, fuses, indicators, battery, etc.) and major
component is removed and replaced, perform the operational test.
Unless a bench mock-up for the AN/ASN-128 has been manufactured,
this task is performed only in the aircraft.
Refer to Aircraft Operator's Manual for proper procedures to
activate aircraft power to provide the power required: 28V dc,
26V 400 Hz, 5V (ac or dc).
To perform the operational checkout, activate the vertical gyro
for roll and pitch data.
Heading data is required from the
It may be necessary to use a hood during
daylight to verify all lighting requirements.
(1) On the Computer Display Unit (CDU), rotate the MODE switch to
lamp test by pulling the MODE switch out and turning it one position
clockwise. (See figure on CDU.) Visually verify that: