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Doc# 2016-25-05 Rev F Technical Support 678-208-3087 Ext #1 Airtext Installation Manual
Coax Iridium Antenna Cable Considerations
RF Path Signal loss is determined by the coax cable type, its length, and condition. Minimize cable
length to preserve signal strength. The total implementation loss for an antenna, connectors, cable,
disconnects, lightning arrestor, and any other RF component between the Airtext router and the antenna
should not exceed 3dB.
Coax Cable Type
Approx. Signal
Loss per 100 ft.
Cable
Diameter inch
Minimum Bend
Radius
PIC S86208 (RG-142)
18.04 dB
.13
.65 inch
Emteq PFLX195-500 (RG-142)
14 dB
.20
.5 inch
PIC S33141 (RG-393)
8.63 dB
.27
1.4 inch
PIC S55122 (RG-393)
6.5 dB
.31
1.55 inch
Emteq PFLX240-500
11 dB
.242
.75 inch
RG-8A (non-aviation)
8 dB
.405
1 inch
Example cable: Pic Wire and Cable Company;
www.picwire.com
Part Number: 34480-4300-04. 10' CABLE ASSEMBLY W/ S33141 CABLE & 190308 TNC Male
Straight connector & 190309 TNC Male Right Angle Connector.
Iridium Antenna Options
Antcom, Cobham/Comant, Sensor Systems… are some of the manufacturers of Iridium antennas. Newer
models of Iridium antennas such as Sensor Systems S67-1575-410 support higher transmit power
capability that may be needed for Iridium Certus
℠
Broadband, available starting in 2019 as Iridium’s
next-generation satellites come online. Dual and Quad antennas are available to permit replacing a single
channel GPS antenna or single channel Iridium antenna with a GPS/Iridium or GPS/multiple iridium that
are designed to use existing mounting hole pattern and existing doubler.
Sharing an Antenna
If there is an existing Iridium antenna on the airplane that is occasionally utilized for a phone it may be
possible to share the antenna with Airtext. This is accomplished with a relay and switch to share the use
of the antenna. The switch should be marked Voice (for phone use) and Data (for Airtext use). For the
STC a Pasternak PE7147 Relay was used. Any similar coax relay would be sufficient.
If antenna sharing is not required, then interface option 1 can be used. If the existing Iridium antenna is to
be shared with the phone, then interface option 2 may be used. Components are: Airtext, an A/B switch, a
coaxial relay, and the Iridium phone antenna. The second interface would require installing an Iridium
antenna. Components are: Airtext and the Iridium antenna.
