Antenna Polarization; Receiver Installation - Spektrum AR9020 User Manual

Patented MultiLink
The AR9020 includes three receivers, offering the security of multiple path RF
redundancy. An internal receiver is located on the main receiver while two required
external receivers are attached to the main board with a 6-inch and a 12-inch ex-
tension. If desired, you can add an optional fourth receiver to offer ultimate security.
Locating these receivers in slightly different locations in the aircraft exposes each
receiver to its own RF environment. This greatly improves the receivers' ability to
see the signal in all conditions.

Antenna Polarization

For optimum RF link performance, mount the antennas in an orientation that allows
for the best possible signal reception when the aircraft is in all possible attitudes
and positions. Orient the antennas perpendicular to each other; typically one
vertical and one horizontal (see Receiver Installation). Mount the remote receivers'
antenna perpendicular at least 2 inches away from the main receiver' s antenna
using double-sided foam tape.

Receiver Installation

Mount each remote receiver at least 2 inches away from the primary antenna.
Ideally, you should position the antennas perpendicular to each other. This gives
tremendous improvements in path diversity as each receiver can „see" a different
RF environment. This is key to maintaining a solid RF link, especially in aircraft
that have substantial conductive materials (e.g., larger gas engines, carbon fiber,
pipes, etc.), which can weaken the signal. In airplanes, we recommend mounting
the primary receiver in the center of the fuselage on the servo tray and the remote
receivers on the side of the fuselage or in the turtle deck.
X-Plus 8 Module Installation
X+1
X+2
X+3
X+4
X+5
X+6
In gas and glow aircraft, install the X-Plus 8 module by wrapping it in protective
foam and fastening it in place using rubber bands or a hook and loop strap. In
electric airplanes or helicopters, you can use thick double-sided foam tape to
fasten the module in place.
When connecting an X-Plus receiver and module, mount them near each other to
minimize current loss. If servo extensions are needed, we recommend using heavy
22 gauge wire with gold-plated connectors.
Auxiliary batteries can be used to support the servos connected to the X-Plus mo-
dule. However, if 1 or 2 auxiliary batteries are connected, never use a jumper plug
in addition to an auxiliary battery. This may damage the module or the receiver. If
no auxiliary batteries are used, install a jumper plug in a BATT/JMPR port.
Receiver Technology
™
7
X+7
X+8
BATT/JMPR
BATT/JMPR
SRXL
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