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Introduction
Phase nulling with two antennas and a phasing unit allows an operator to hear a desired signal by
reducing or completely removing a much stronger interfering signal arriving from a different
direction, without affecting the desired signal. Ideal for Amateur Radio, Shortwave Listening or
Broadcast AM DX reception, the
DXE-AAPS3-1P
Active Antenna Phasing System (
AAPS
) offers
excellent directional receiving performance from 500 kHz to 15 MHz using two high quality
DXE-ARAV3
vertical receive antennas working in conjunction with the outstanding
DXE-NCC-1
Receive Antenna Variable Phasing Unit.
DX Engineering’s unique design is vastly superior to traditional active antennas in both strong
signal handling and feedline decoupling, providing significantly better weak signal reception due to
lower spurious signal interference and reduced noise. Coupled with the
DXE-NCC-1
Receive
Antenna Variable Phasing Unit, this package makes up a complete electronically rotatable receive
antenna system.
THIS IS A RECEIVE-ONLY SYSTEM
You should
never
attempt to transmit through the system.
The use of bypass relays and sequential timing is required to avoid damage to the
active receive antenna system.
Placing the active receive system on the same mast or tower as the transmit
antenna is
not
recommended.
This compact receiving antenna system operates over a very wide bandwidth with superior strong
signal performance. The output Third Order Intercept (TOI) is approxi30 dBm. This is
significantly better than most aftermarket preamplifiers and receivers - making it one of the cleanest
active antennas on the market, reducing or eliminating spurious signals.
Feedline decoupling, absent in some other popular designs, is also exceptionally good. Decoupling
the shield greatly reduces feedline conducted noise and unwanted signal interference
Any receive system can be affected by local noise sources. Local noise can be random or directional
in nature. First, every effort must be made to locate sources of noise that could be eliminated at the
source. Dimmer switches, electric timers, photocell-operated security lights, and many other items
can be sources of unwanted noise. Plasma-screen television receivers are becoming more popular
and are a known generator of unwanted noise interference. When the noise source is directional in
nature, using the two
DXE-ARAV3
receive antennas in conjunction with the
DXE-NCC-1
allows
the user to phase out the noise being received.
Ideally your receive antennas should be a minimum of 1/2-wavelength away from any transmit
antenna (on the lowest frequency) to avoid mutual coupling and the transfer of any noise being
passively re-radiated by the transmit antenna. The
DXE-ARAV3
series active vertical antenna
system also grounds the receive antenna element when power is turned off for protection of the
active devices.
The
DXE-ARAV3
active receive antennas, used in the
DXE-AAPS3
package, may be used in
