11
Delay lines DLY1 and DLY2 must be half the length of DLY3
. Make DLY1 and DLY2 as close
to half the physical length of DLY3 as possible. To avoid performance degradation due to
inconsistent coax construction, all the delay line coax should be cut from the same spool.
Delay line cables can be neatly coiled in a 1-1/2 ft diameter coil. Support the weight of the cables
by taping or securing them to the support pole or mast rather than allowing them to hang from the
connectors. It is important to use 75 Ω feedline to the operating position from the
DXE-RFS-3
. Do
not use amplifiers, combiners, filters or splitters that are not optimized for 75 Ω systems.
Active Antenna Feedlines
Use 75 Ω coax from each antenna element to the
DXE-RFS-3
. The four feedlines from the
DXE-
RFS-3
phasing unit to the active elements can be any length needed to accommodate the size of the
array, but must all be the same length, velocity factor and type. Note the orientation and numbering
of the elements by using
Figure 2
.
Be sure the appropriate antenna element is connected to the
proper ANT connector on the phasing unit. The default (zero control voltage) forward direction is
towards Element 1. Element 3 is the rear or null direction.
Control and Power Connections
The
DXE-RFS-SYS-2P
system, with the
DXE-EC-4
BCD Control Console, no other equipment is
needed for powering the
DXE-RFS-3
, the active elements or controlling the receive direction.
J12
is the 5-terminal connector plug on the front panel of the
DXE-RFS-3
. It is labeled
G A B C G
.
The
DXE-RFS-3
uses a two part green connector and the top part can be removed by pulling it
straight off. This will allow easier wire replacement or servicing as needed. When pushing the
connector back in place, ensure you press straight inward.
The
DXE-EC4
uses an internal terminal plug labeled “G 1 2 3”.
DXE-EC-4
DXE-RFS-3
G
to
G
1
to
A
2
to
B
3 *
to
C *
Wire connections between the
DXE-EC-4 and DXE-RFS-3
* In a passive array system, the wire from EC-4
connection 3 to RFS-3 Connection C is not required.
