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the noise along with the signal.
It is always best to use the least gain possible
. Depending on
conditions, a preamplifier can cause receiver overload; this may require an attenuator or bypassing
the preamplifier.
The
DXE-RPA-1
HF Preamplifier has better dynamic range than most receivers and can be used to
compensate for the decrease in array signal output. The
DXE-RPA-1
preamplifier is automatically
bypassed when power is removed.
Front-to-Rear (Null) Optimizing
The
DXE-RFS-2
is factory adjusted
to the correct settings for most coaxial
cables. In some cases, the null depth
may need to be adjusted to
compensate for inaccurate delay line
lengths. To adjust the null depth, tune
to a strong steady signal off the back
of the antenna’s selected direction and
adjust R4 and R8 for the deepest null
(weakest signal off the back). Use
Figure 5
to locate R4 and R8 near the
center of the circuit board.
Operation
When using the
DXE-RFS-2
,
positions 5 though 8 on the
CC-8A
Control Box will phase the
appropriate active vertical elements to
give you excellent receiving
capabilities.
The front to back signal to noise ratio
of the active vertical elements in the
four phase array allow you to not only
enhance the desired received signal,
but also to decrease an unwanted
receive signal by selecting a position
that will drastically reduce or eliminate it.
