Electromagnetic Interference (Emi) Check - Garmin GI 275 Installation Manual

6.7

Electromagnetic Interference (EMI) Check

An EMC check must be conducted once the GI 275 system is installed and all interfaces to external
equipment are verified to be working correctly. The EMC check verifies that the GI 275 is not producing
unacceptable interference in other avionics systems and other avionics systems are not producing
unacceptable interference in the unit.
1. Enter equipment installed in the aircraft into the Source row and Victim column of the form.
2. Apply power to all avionics systems except for the components that are considered to be part of the
GI 275 system.
3. Verify all existing avionics systems are functioning properly.
4. Apply power to the GI 275 system components.
5. Remove power from all other avionics systems.
Before applying power to the next system, wait for the current system start-up sequence to finish.
6. Apply power and/or operate the systems listed on the fillable form, one system at a time.
7. Verify the GI 275 system functions properly. Verify there are no related messages displayed.
8. Verify each radio is functioning properly by completing the following:
a. For each VHF COM radio, monitor one local frequency, one remote (far field) frequency, and
one unused frequency.
a. Verify no unintended squelch breaks or audio tones interfere with communications.
b. For each VHF NAV radio, monitor one local frequency, one remote (far field) frequency, and
one unused frequency.
c. Verify there are no guidance errors.
d. Verify no audio tones interfere with the station ID.
9. If an EI FT-60 or an EI FT-90 fuel flow sensor is installed, verify the fuel flow indication is
accurate and the indication does not fluctuate or invalidate the display.
a. Transmit various modulating tones on each COM radio (e.g., whistling).
b. Refer to Section 4.7.6.1 for details if the fuel flow indication fluctuates.
10. Verify all other avionic systems are functioning properly.
190-02246-10
Rev. 11
GI 275 Part 23 AML STC Installation Manual
Page 6-36