3.8.3
Performance (Ramp) Test
CAUTION
If the unit is removed from the aircraft and operated, always connect J2302 to an
antenna or a 50 Ω, 5-Watt load. The GTX 23 transmits Mode S acquisition
squitters about once per second whether interrogations are received or not. The
unit may become damaged if J2302 is not connected to a 50 Ω, 5-Watt load when
the unit squitters,
Installations require verification of proper operation of the transponder by testing as specified in
Appendix F of 14 CFR, Part 43, to AC 43-6B, and/or other appropriate regulations. The test is typically
done as a ramp test using a transponder ramp test set, such as the TIC TR-220, IFR ATC-601 or other
suitable Mode S transponder test set. The ramp test includes checks as follows:
Reference Part 43 Appendix F:
a. Reply Frequency
b. Suppression
c. Receiver Sensitivity
d. Reply RF Output Power
e. Mode S Diversity Channel Isolation (if applicable)
f.
Mode S Address
g. Mode S Formats
h. Mode S All-Call
i.
ATCRBS –Only All Call
j.
Squitter
Reference AC 43-6B and 14 CFR Part 43, Appendix E (c):
a. Altitude Reporting
3.9 Continued Airworthiness
Installations are required to test according to Title 14 CFR §§ 91.411 and 91.413 as well as Part 43
Appendix F. Otherwise, maintenance of the GTX 23 is 'on condition' only.
190-00906-01
Rev. C
GTX 23 Installation Manual
Page 3-4