m. Plug the wall charger jack into the charger socket at the rear of the GPS 155. Verify that the
Battery Test Page indicates “TRICKLE CHARGE”.
n. Unplug the wall charger jack from the GPS 155. Verify that the Battery Test Page indicates “RAPID
CHARGE”.
o. Allow sufficient time for the external NiCad battery to charge. If the battery is fully discharged, this may
take up to 1.5 hours. After the battery is charged, the Battery Test Page should indicate “MAINT
CHARGE”. A failure is indicated any time the Battery Test Page indicates “NO CHARGE”.
p. Turn the FUNCTION SELECT switch on the test panel to position #13.
q. Monitor the external NiCad battery voltage on the DMM.
r.
Push the UNIT POWER switch on the test panel to turn off external power to the GPS 155. Verify that
the Battery Test Page indicates “REMOTE BATT OK”. (The Battery Test Page indicates “REMOTE BATT
TMP OK” when using wall charger power.) A failure is indicated when “OVR TMP” is displayed.
s. Turn the FUNCTION SELECT switch to position #12. Verify that the DMM voltage is less than 0.5 VDC.
13. GPS Receiver Noise Test:
a. Depress the ENT key while powering up the unit. THis puts the unit into Test Mode.
b. Rotate the outer function knob until the Receiver Test Page is displayed:
c. Terminate the GPS receiver’s antenna connection into a 50 ohm load.
d. The bottom line of the display represents the receiver noise level. Verify that this number is within the
range of 1800-2200.
14. Operational Test:
a. Turn the GPS 155 OFF.
b. Insert a Jeppesen NavData® card.
c. Turn the GPS 155 ON normally, without entering test mode. Verify that the GPS 155 passes its self test.
A failure is indicated by one of the messages listed in Section 2.2.
d. Verify that the GPS 155 correctly reads the NavData® card and indicates the type,
effective date and expiration date.
e. Press the ENT key and verify that the Satellite Status Page is displayed.
f.
Press the MSG key and verify that the Message Page is displayed.
g. Press the Direct To key and verify that the GO TO Page is displayed.
h. Rotate the inner function knob to select a letter or number on the display.
i.
Press the CLR key and verify that the selected letter/number disappears.
j.
Press the NRST key. Verify that a Nearest Waypoint Page is displayed and the
annunciator next to the SET key is on.
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