DX Engineering DXE-RFCC-1 Instruction Manual

Feedline Current Choke

1200 Southeast Ave. - Tallmadge, OH 44278 USA

Phone: [phone] ∙ Tech Support and International: [phone]

Fax: [phone] ∙ e-mail: [e-mail]

Receive

RFCC-1

DXE-RFCC-1-INS-Revision 3

 DX Engineering 2020

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Introduction

The DX Engineering RFCC-1 receive feedline common-mode choke is the most effective solution
to common-mode noise or unwanted signal ingress available to date. The DX Engineering RFCC-1
provides thousands of ohms isolation between the input and output coaxial shield connections while
passing desired signals, including dc or low frequency ac control signals. The RFCC-1 has
extremely high isolation impedance which effectively blocks common-mode noise or unwanted
signals, even in the presence of very poor grounding.

The RFCC-1 is effective from 300 kHz to 30 MHz. It comes with standard CATV type “F” female
connectors, although it can be used in any 50 to 75 ohm receiving system. The RFCC-1 is a passive
device, therefore requires no power to operate.

Application

Low noise receive antennas are traditionally located away from electrical wiring and other noise
sources. Unfortunately, noise and other unwanted signals have a direct path to your low-noise
antenna through the feedline shield connections between the station equipment and antenna.
Unwanted signals can also energize the outside of the feedline shield, and this undesired signal
energy can be conducted directly to the receiving antenna. This can reduce antenna directivity.
Unless you have a perfect zero-resistance RF ground at the antenna, some of the common-mode
noise or unwanted signals from the feedline shield will make it into the antenna. While RF
suppression beads over the feedline can help, their impedance is generally very low, limiting the
amount of isolation they can provide. Bead effectiveness is significantly dependent on feedline and
antenna grounding.

Do not transmit through the RFCC-1 as damage to the unit will occur.

Note: The DXE-RFCC is not recommended for use with the DXE-RF-PRO-1B since there is large
amount of current drawn by the RF-PRO-1B which will cause a severe voltage drop if the RFCC is
used. An alternate solution would be to use #31 ferrite cores to create a common mode choke with
nine wraps of coax.

Installation

One of the RFCC-1 connectors is isolated from the case and can be identified by the white washer
under the connector. The other connector is grounded to the case. The longest feedline cable run
should always be attached to the grounded connector, and the RFCC-1 should always be grounded
to its own independent ground rod. We recommend at least one ½ to ¾” diameter copper ground
rod at least 5 feet long.

The optimum location for the RFCC-1, in most applications, is near the antenna. Place the RFCC-1
close to the antenna, but before the feedline parallels any antenna element. For a small loop antenna
with the feedline dropping vertically from the loop, install the RFCC-1 approximately one to two
loop diameters below the loop.

If you have a Beverage, Flag, Pennant, or K9AY antenna, install the RFCC-1 15 to 30 feet away.

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When the RFCC-1 is mounted near the antenna, the grounded connector should be used for the
feedline going to the operating position. If you mount the RFCC-1 near a building entrance, the
grounded connector should connect to the feedline going to the antenna. In all cases a separate
isolated ground rod dedicated to the RFCC-1 should be connected to the RFCC-1 ground post.

Receiving antenna products from DX Engineering, such as the Active Receive Antenna system,
include internal common-mode isolation between the feedline shield and antenna. If additional
isolation is needed, the RFCC-1 should be installed 20-30 feet from the antenna.

Figure 1 - RFCC-1 Shown in a Four -Direction Reversible Beverage System

Figure 2 - RFCC-1 Shown in a Receive Four-Square Array

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Technical Support

If you have questions about this product, or if you experience difficulties during the installation,
contact DX Engineering at [phone]. You can also e-mail us at:

[e-mail].

For best service, please take a few minutes to review this manual before you call.

Warranty

All products manufactured by DX Engineering are warranted to be free from defects in material and workmanship for a
period of one (1) year from date of shipment. DX Engineering’s sole obligation under these warranties shall be to issue
credit, repair or replace any item or part thereof which is proved to be other than as warranted; no allowance shall be
made for any labor charges of Buyer for replacement of parts, adjustment or repairs, or any other work, unless such

charges are authorized in advance by DX Engineering. If DX Engineering’s products are claimed to be defective in

material or workmanship, DX Engineering shall, upon prompt notice thereof, issue shipping instructions for return to
DX Engineering (transportation-charges prepaid by Buyer). Every such claim for breach of these warranties shall be
deemed to be waived by Buyer unless made in writing. The above warranties shall not extend to any products or parts
thereof which have been subjected to any misuse or neglect, damaged by accident, rendered defective by reason of
improper installation, damaged from severe weather including floods, or abnormal environmental conditions such as
prolonged exposure to corrosives or power surges, or by the performance of repairs or alterations outside of our plant,

and shall not apply to any goods or parts thereof furnished by Buyer or acquired from others at Buyer’s specifications.

In addition, DX Engineering’s warranties do not extend to other equipment and parts manufactured by others except to

the extent of the original manufacturer’s warranty to DX Engineering. The obligations under the foregoing warranties

are limited to the precise terms thereof. These warranties provide exclusive remedies, expressly in lieu of all other
remedies including claims for special or consequential damages. SELLER NEITHER MAKES NOR ASSUMES ANY
OTHER WARRANTY WHATSOEVER, WHETHER EXPRESS, STATUTORY, OR IMPLIED, INCLUDING
WARRANTIES OF MERCHANTABILITY AND FITNESS, AND NO PERSON IS AUTHORIZED TO ASSUME
FOR DX ENGINEERING ANY OBLIGATION OR LIABILITY NOT STRICTLY IN ACCORDANCE WITH THE
FOREGOING.

©DX Engineering 2020

DX Engineering®, DXE®, DX Engineering, Inc.®, Hot Rodz®, Maxi-Core®, DX Engineering THUNDERBOLT®, DX
Engineering Yagi Mechanical®, EZ-BUILD®, TELREX®, Gorilla Grip® Stainless Steel Boom Clamps, Butternut®,
SkyHawk™, SkyLark™, SecureMount™, OMNI-TILT™, RF-PRO-1B®, AFHD-4® are trademarks of PDS Electronics,
Inc. No license to use or reproduce any of these trademarks or other trademarks is given or implied. All other brands
and product names are the trademarks of their respective owners.

Specifications subject to change without notice.

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