DX Engineering DXE-RR8B-SD Instructions manual

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RR8B-SD

8-Port High Power Remote Antenna Switch

DXE-RR8B-SD-INS-Revision 1e

 DX Engineering 2022

1200 Southeast Ave., Tallmadge, OH 44278 USA

Phone: [phone]  Technical Support and International: [phone]

Fax: [phone]  E-mail: [e-mail]

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Introduction

The DXE-RR8B-SD is the largest switch in the DX Engineering RR8 series. It is designed to
switch coaxial lines in high-power RF systems. RF rated enclosed relays with wide contact gaps
provide exceptional RF voltage and current capability. The RR8B-SD can be used to
simultaneously select multiple output ports as well as conventional one-of-eight antenna switching.
This allows the RR8B-SD to be used in complex antenna phasing and stacking systems as well as
traditional switching arrangements. The RR8B-SD also uses a removable screw terminal control
cable plug. The removable plug greatly simplifies installation by eliminating the need for soldering.
Disassembly is not required for control wiring access

The RR8B-SD also offers the following features:

• RF Shielded Weatherproof Housing - unique protection

• Excellent Port Isolation; greater than 60 dB at 30 MHz, worst case.

• High-RF tolerant, Amphenol UHF connectors

• Shorted or open selection of unused antenna ports

• Enclosed 25-ampere high-voltage RF relays

• Safe 12-volt relay operation

• MOV Lightning protection on control lines

Specifications

Power Rating: >10 kW normal amateur operation on all modes when using antennas with less than

2:1 SWR on 30 MHz and below. >5 kW above 30 MHz.

Control Voltage: 10-14 Vdc at 160 mA
Port-to-Port Isolation: >60 dB below 30 MHz
Impedance: 50 ohms
Control Line: Control lines can normally use good quality CAT5e cable (4 twisted pairs of 24

AWG wire) for runs up to 1000 feet. Typical DX Engineering control lines requirements are +12
VDC at 25 milliamps. Depending on the number of control lines needed (usually 3 or 4) you can
double up the twisted pairs of CAT5e cable, or use control wire that is at least 22 AWG, allowing
runs up to 1500 feet. If you use a cable with more conductors, it is a good idea to tie the unused
conductors to ground. For longer runs of control cable, use a line loss calculator to ensure you
supply the proper control levels needed.

Approximate Control Line Lengths.

Minimum Copper

Wire Gage (AWG)

Length

24

1,000 feet

22

1,500 feet

20

2,000 feet

Theory of Operation

The RR8B-SD uses a star arrangement of eight relays to select one or more of eight output ports
when voltage is applied from an 8-wire control line. The eight RF-rated relays provide greatly
improved power handling and SWR over conventional switches and allows port-to-port connections
between any of the eight output ports.