User's Manual

190-01561-00
GIA 6300 Installation Manual
Draft1
Page 3
3 Installation Overview
3.1 Cabling and Wiring
Coaxial cable with 50 Ω nominal impedance and meeting applicable aviation regulations should be used
for the installation. A typical maximum cable length for the GPS antenna is 40 feet. The installer shall
insure that the attenuation of the GPS cable run falls between 3 dB and 7 dB inclusive at 1.5 GHz.
3.2 VHF COM Cable Routing
Avoid routing the COM antenna cable near aircraft control cables or near GPS antenna cables. Avoid
sharp bends in the antenna cable.
Check for insertion loss and Voltage Standing Wave Ratio (VSWR). VSWR should be checked with an in-
line type VSWR/wattmeter inserted in the coaxial transmission line between the transceiver and the
antenna. The VSWR meter should be inserted as close to the transceiver as possible. Any problem with
the antenna installation is most likely seen as high reflected power. A VSWR of 3:1 may result in up to a
50% loss in transmit power. VSWR at the low, mid and high end of the tuning range should be less than
3:1, for best performance VSWR should be less than 2:1. A high VSWR decreases the amount of power
radiated by the antenna and increases power supply current and heat dissipated by the radio when the
radio is transmitting.
4 Cooling Accessory
The GIA 6300 requires cooling accessory, 011-03516-00, for normal operation. This cooling accessory
contains 4 fans, powered by the GIA Main Boards. Main A powers 2 of the fans, and Main B powers the
other 2. The GIA 6300 can operate at full functionality with up to 2 fan failures.
A ported version of the cooling accessory could be considered/designed if desired by an OEM.