Trig Avionics 01629-00, Руководство по установке

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TT26 ADS-B Transponder Installation Manual 24 January 2017
01633-00 Issue AC
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18 Trig Avionics Limited
connectors should be less than 10dB.
5.10 Transponder Antenna
The TT26 is compatible with any transponder antenna approved to ETSO or
TSO C74 or C112.
5.11 Transponder Antenna Cable
A low loss cable terminating at the transponder in a TNC connector is required.
The TT26 is designed to meet Class 1 requirements with an allowance of 2 dB
for loss in the connectors and cable used to connect it to the antenna.
Excessive loss will degrade both transmitter output power and receiver
sensitivity.
Allowing 0.25dB loss for the connector at each end of the antenna cable
assembly leaves an allowance of 1.5dB maximum loss for the cable itself. An
acceptable cable:

Has less than 1.5dB loss for the run length needed

Has a characteristic impedance of 50 Ohms

Has double braid screens or has a foil and braid screen
For cable runs of less than 2.5 metres, RG400 is a good choice.
5.12 Static Pressure Connection
The TT26 includes an altitude encoder which must be connected to the same
source of static pressure as the primary altimeter on the aircraft. The TT26
static pressure port provides a mounting spigot intended for nominal 3mm or
1/8 inch inside diameter tubing.
In all cases, the static line should include drainage provisions and should be
routed in accordance with CS 23.1325 or other applicable airworthiness
provisions for the aircraft.