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Introduction
The DX Engineering
DXE-RPA-2
Modular Receive Preamplifier is a high-performance broadband
LF through HF receiver preamplifier that features exceptional immunity to overload. It also has an
excellent noise figure and a low input SWR, optimized for the 300 kHz to 35 MHz range.
Meticulous craftsmanship and durable, robust
components allow this 50-ohm preamplifier to
withstand high signal levels while providing
superior dynamic range and third-order intercept
performance that equals or exceeds most receiver
and transceiver front-ends. Unlike other external
preamplifiers and many transceiver internal
preamplifiers, the RPA-2 enhances the readability
of weak signals without artificially increasing the
noise. On low bands and beyond, weak signals
become more intelligible using this preamplifier
in conjunction with proper adjustment of the RF Gain and Attenuator in the transceiver.
The RPA-2 is a combination of a redesigned aluminum shielded enclosure chassis with the
DXE-
RPA-2-PM
Receive Preamplifier Plug-in Module factory installed. The
DXE-RPA-2-PM
module
retains the essential characteristics of the milestone product, the original DX Engineering RPA-1.
Featuring an internal optional module slot, the RPA-2 allows the use of the optional
DXE-IT-PM
75 to 50-ohm Impedance Transformer Plug-in Module or the optional
DXE-RG5000HD-PM
Receiver Guard Plug-in Module.
While many other common preamplifiers suffer from harmonic distortion, the
DXE-RPA-2
low-
noise preamplifier features an advanced push-pull design that eliminates harmonic distortion. High
quiescent current increases its ability to handle strong signals without distortion or overload. This
high performance device must be powered with a well filtered and regulated DC power supply and
offers maximum performance at +13.8 Vdc to +18 Vdc input. Never use an inexpensive, poorly
performing wall transformer to power this top-of-the-line preamplifier.
Features
Internal circuit impedance of 50-ohms for direct connection to 50-ohm receive systems and
antenna feedline BNC connectors with no transformer required
Internal slot accommodates the optional 75 to 50-ohm Impedance Transformer Module to
accomplish transition from a typical F connector 75-ohm receive antenna feedline to 50-ohm
equipment, without losses
Input and output connectors BNC and F types, prevent accidental connection to transmitting
devices
Automatic RF bypass relay also turns the preamp off when the dc power is removed
Green LED indicates when DC power is present and the preamplifier circuit is engaged
An ingenious positive-capture threaded-sleeve 2.1 mm power connector that ensures the DC
power cannot be accidently disconnected from the RPA-2
A simple internal jumper allows the RPA-2 to be powered by DC on the feedline for use on
antenna types that require a preamplifier at the antenna such as Pennants, Flags or K9AY Loops
