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contact connections at low currents. This is because of the large surface areas and hard contact
materials necessary to support high contact switching currents.) The
RCA8C-1
Receive Eight
Circle Array Controller uses sealed relays optimally sized for receiving applications. Contacts are
bifurcated and gold-flashed, substantially improving low signal level switching reliability. The
improved low-level signal optimized bifurcated contacts virtually eliminate non-linearity,
rectification, and other maladies caused by poor relay connections.
The DX Engineering
ARAV4
Active Receive Verticals have excellent broadband receiving
performance from 100 kHz to 30 MHz. In addition, they provide a clean, low profile installation.
DX Engineering’s unique design makes it vastly superior to other amplified and traditional active
antennas in both strong signal handling and feedline decoupling. You get significantly better weak
signal reception due to lower spurious signal interference and reduced noise.
Frequency Coverage -vs.- Element Type
The Eight Circle Array uses eight elements to form a clean, narrow beamwidth, low-angle pattern in
eight equally spaced user selectable directions. The elements form the most space-efficient type of
directional array, a broadside-endfire combination. With broadband active elements that are created
with the DX Engineering Active Receive Verticals, this array has an exceptionally good pattern
over at least a 3:1 frequency range. With these broadband active elements this array has unbeatable
performance across a single band.
The Eight Circle Array upper frequency limit for a clean unidirectional pattern is slightly above
where the array is .35-wavelength radius. The frequency of optimum performance is where the
array is approximately .327-wavelength radius. Construction care, element construction, desired
beamwidth, and local noise floor determines the minimum array size in wavelengths. Minimum
useful frequency typically occurs with an array less than 0.1-wavelength radius; although that limit
can be pushed lower with care in some situations. Careful construction will allow useful directivity
over the entire HF range with an exceptionally good pattern over a 3:1 frequency range.
A Special Application
The DX Engineering
DXE-RCA8C
Eight Circle Array phasing and switching system may also
be used as a unidirectional or bidirectional end-fire/broadside array with the installation of only
four vertical elements, using 1/10 to 1/4-wavelength endfire spacing in combination with 1/4 to
3/4-wavelength broadside spacing.
This limited implementation is for the user who specifically wants a very directional receive
antenna system that is pointed only in one direction, without power required, similar to a single
direction, phased Beverage array. It would also be switchable to a second opposite direction
with DC power, similar to a very long Reversible Beverage.
However, this Active Element end-fire/broadside array alternative to building a phased
Beverage array requires a lot less space and a lot less maintenance! Contact DX Engineering for
more details on the use of the
DXE-RCA8C
for a four element system.
Summary of Contents for DXE-RCA8C-SYS-4S
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