3
Introduction
The DX Engineering
DXE-RTR-2
Modular Receive Transmit Interface
is an innovative, multi-
purpose relay unit that automatically switches the RF output connector on any HF transceiver
between a receiving antenna system and a standard transmitting antenna. A front panel mode switch
allows the operator to listen to either antenna system.
It provides the safest and most versatile
method of connecting a receive antenna to any general coverage receiver, but it most often used
with HF transceivers that do not have a separate receive antenna input.
The
DXE-RTR-2
has a new design that features three internal slots for optional accessory modules
to improve receive system connections, provide receiver front-end protection and to dramatically
enhance low-signal receive antenna performance.
75 to 50 ohm Impedance Transformer Plug-in Module,
DXE-IT-PM
Receiver Guard Plug-in Module,
DXE-RG5000HD-PM
Receive Preamplifier Plug-in Module,
DXE-RPA-2-PM
The
DXE-RTR-2
is a very useful
antenna relay unit for many
applications, such as adding our low-
noise, high dynamic range receive
preamplifier to any transceiver or
receiver, as requested by Amateurs
and SWLs. Or, add failsafe receiver
protection for stations with close-
spaced transmit and receive antennas.
This unit protects and safely connects
any transceiver to any antenna that
can be used for receiving, including
Beverage, Pennant, Flag, a passive
loop or a sophisticated Receive
Array. Plus, it supplies keyed, bias-
tee voltage on the receive antenna input for all types of powered receive antennas including the
Active Receive Vertical,
DXE-ARAV3-1P
and the Active Magnetic Loop,
DXE-RF-PRO-1B
.
One of the most important features of the
DXE-RTR-2
is its unique, failsafe relay system that
protects the unit, the plug-in modules, and the receive antenna equipment from transceiver RF
output damage. The receive antenna mode (RX ANT) is only allowed when the dual-purpose
keying line from the transceiver is connected, carrying the special RX ENABLE output signal on
the keying line
shield
to the transceiver chassis. This is the failsafe interlock. Then, as soon as the
transceiver is keyed (
or
the unit loses power), the RF output from the transceiver is automatically
diverted to the transmit antenna connection. The very fast acting relay (about 4 ms) in the RTR-2
diverts the transceiver output (up to 200 watts CW) fast enough for QSK, full break-in CW (use
partial break-in CW operation when using Bias Tee powered active receive antennas), while
listening to a receive antenna. It prevents the hot switching and timing errors that are common on
other transmit/receive relays, especially dangerous RF sense circuits.
