DX Engineering DXE-DMC-2 Instructions manual

Dual Module Chassis

DXE-DMC-2

DXE-DMC-2-INS Revision 1a

© DX Engineering 2020

1200 Southeast Ave. - Tallmadge, OH 44278 USA

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

Fax: [phone] ∙ E-mail: [e-mail]

Introduction

The DX Engineering Dual Module Chassis (DXE-DMC-2) is the connector and power interface
box for all DX Engineering Plug-In Modules and Receive Filters. This is one of the most highly
requested DX Engineering accessories. You can build a special HF receive filter or create a wide
pass filter, protect a receiver with a filter and a limiter or make a preamplifier with filtering or
limiter protection.

Features of the DXE-DMC-2 Dual Module Chassis:

 Attractive black aluminum enclosure
 Green LED for Power On indication
 Two internal option slots for Plug-In Modules
 Receive Antenna Input, Receiver Output – BNC for 50 ohm and F connector for 75 ohm

feedlines (use 75 to 50 ohm Impedance Transformer Plug-In Module - DXE-IT-PM)

 Internal jumper to enable bias-tee DC power injection onto receive feedline for active

preamplifier plug-in option

 Screw-on version of the DC power connector is provided to prevent accidental power cable

pull-out (standard type 2.1 mm DC power connector may be used)

 Operates on +13.8 Vdc nominal

.

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To open the unit, remove the 6 Phillips head screws to open the unit. Remove the cover. You will
then see the main PCB and the by-pass module installed.

The DXE-DMC-2 is a versatile multi-purpose DX Engineering receive device box. It can be used
for two passive plug-in modules or one powered module and one passive module. The top slot is
first in line from the Antenna Input, paralleled BNC and F connectors.

Next in line is the bottom slot that feeds the two parallel Receiver Output connectors, F and BNC.
This position has voltage available for an active plug-in module such as the DXE-RPA-2-PM
Receive Preamplifier Plug-in Module.

One bypass card is supplied to install in either unused slot when only
one module is used.

Available passive modules include the limiter, the transformer and many types of filters. The
preamplifiers are powered modules.

When used, a preamplifier plug-in module is typically powered by a + 13.8
Vdc station supply using the supplied 2.1 mm screw-on connector or a
standard 2.1 mm connector. Turning off the power bypasses the received
signal around the preamplifier module, allowing reception without pre­amplification.

Alternatively, if the DXE-DMC-2 unit is used as a weather­protected remote preamplifier, an internal jumper change
enables the preamp module to be powered by an in-shack
voltage inserter on the DXE-DMC-2 Receiver Output
feedline.

Note: There is no Bias-Tee available to the Antenna Input for
active antennas with his unit.

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Installing Optional Plug-In Modules

Part Number

Description

DXE-IT-PM

75 to 50 ohm Impedance Transformer Plug-in Module (passive)

DXE-RG5000HD-PM

Receiver Guard 5000HD Plug-in Module (passive)

DXE-RPA-2-PM

Receive Preamplifier Plug-in Module (powered)

DXE-RXFL-1

Receive Filter Adapter Board, for RXFL Filters (passive)

DX Engineering optional modules used with the Dual Module Chassis:

DXE-IT-PM DXE-RG5000HD-PM DXE-RPA-2PM

Open the unit by removing the 6 Phillips head screws and
remove the cover.

The picture shows the cover removed and two optional
plug-n boards ready to install.

Remove the by-pass jumper PCB in the bottom slot by gently using a straight shaft screwdriver on
each side of the PCB. Pull one side loose, then the other side as shown below.

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This example shows installing the optional DXE-RG5000HD-PM plug-in module. Place the board

on the pins and push the PCB until it fully seats in place.

The optional filter board needs to be installed on the DXE-RXFL-1 Receive Filter Adapter Board.
Install your optional filter board by pressing it filly in place on the Adapter Board. Insure you have
the pins properly aligned as shown.

The optional Filter Board and Adapter board are then installed in the DMC-2 by aligning the board
pins an pressing evenly until the board is fully seated in place.

Optional Filters, the DXE-RG5000HD-PM and DXE-IT-PM can be installed in either slot.

If you are installing the optional DXE-RPA-2PM preamplifier, it must be installed in the bottom
slot. The bottom slot has DC power available. The top slot does not have DC power available.

If a slot is not used, the jumper PCB should be installed.

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One optional DXE-RXFL-1 Receive Filter Adapter Board is required to

Filter Part Number

Description

DXE-RXFL-HP160M

High Pass Filter, Roll-Off below 1.8 MHz

DXE-RXFL-HP80M

High Pass Filter, Roll-Off below 3.5 MHz

DXE-RXFL-HP40M

High Pass Filter, Roll-Off below 7.0 MHz

DXE-RXFL-HP20M

High Pass Filter, Roll-Off below 14.0 MHz

DXE-RXFL-HP15M

High Pass Filter, Roll-Off below 21.0 MHz

DXE-RXFL-HP10M

High Pass Filter, Roll-Off below 28.0 MHz

DXE-RXFL-LP160M

Low Pass Filter , Roll-Off above 2.0 MHz

DXE-RXFL-LP80M

Low Pass Filter , Roll-Off above 4.0 MHz

DXE-RXFL-LP40M

Low Pass Filter , Roll-Off above 7.3 MHz

DXE-RXFL-LP20M

Low Pass Filter , Roll-Off above 14.4 MHz

DXE-RXFL-LP15M

Low Pass Filter , Roll-Off above 21.5 MHz

DXE-RXFL-LP10M

Low Pass Filter , Roll-Off above 29.7 MHz

DXE-RXFL-BPF160M

Band Pass Filter, Roll-Off below 1.8 MHz and above 2.0 MHz

DXE-RXFL-BPF80M

Band Pass Filter, Roll-Off below 3.5 MHz and above 4.0 MHz

DXE-RXFL-BPF40M

Band Pass Filter, Roll-Off below 7.0 MHz and above 7.3 MHz

DXE-RXFL-BPF20M

Band Pass Filter, Roll-Off below 14.0 MHz and above 14.4 MHz

DXE-RXFL-BPF15M

Band Pass Filter, Roll-Off below 21.0 MHz and above 21.5 MHz

DXE-RXFL-BPF10M

Band Pass Filter, Roll-Off below 28.0 MHz and above 29.7 MHz

install any one of the optional RXFL filters listed below. They are used in the
DXE-DMC-2, DXE-NCC-2, DXE-RTR-2 and DXE-RPA-2.

The DXE-DMC-2 can accommodate one or two filters to create the filter
type and input signal band pass frequency coverage and limitations that serves your needs. Filter
roll-off frequency is the point where attenuation begins to increase typically to over than 50 dB.
Receive filters are excellent reception improvement tools. They reduce most of the interfering noise
and signals on the attenuated frequencies from entering the front end of the receiver. Reducing the
noise floor of the receiver allows better reception on desired frequencies.

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Filter Graphs

The following 18 charts show the response curves for the 18 optional filters that are available for
the DXE-DMC-2.

DXE-RFXL-LP160M - Low Pass, 160 M and below - Cut off Frequency 2.30 MHz

DXE-RFXL-LP80M - Low Pass, 80 M and below - Cut off Frequency 4.00 MHz

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DXE-RFXL-LP40M - Low Pass, 40 M and below - Cut off Frequency 7.50 MHz

DXE-RFXL-LP20M - Low Pass, 20 M and below - Cut off Frequency 15.00 MHz

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DXE-RFXL-LP15M - Low Pass, 15 M and below - Cut off Frequency 22.00 MHz

DXE-RFXL-LP10M - Low Pass, 10 M and below - Cut off Frequency 30.00 MHz

9

DXE-RFXL-HP160M - High Pass, 160 M and above - Cut off Frequency 1.65 MHz

DXE-RFXL-HP80M - High Pass, 80 M and above - Cut off Frequency 3.40 MHz

10

DXE-RFXL-HP40M - High Pass, 40 M and above - Cut off Frequency 6.60 MHz

DXE-RFXL-HP20M - High Pass, 20 M and above - Cut off Frequency 13.70 MHz

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DXE-RFXL-HP15M - High Pass, 15 M and above - Cut off Frequency 20.20 MHz

DXE-RFXL-HP10M - High Pass, 10 M and above - Cut off Frequency 27.90 MHz

12

DXE-RFXLBPF160M - Band Pass, 160 M only - Center Frequency 1.85 MHz

DXE-RFXL-BPF80M - Band Pass, 80 M only - Center Frequency 3.70 MHz

13

DXE-RFXL-BPF40M - Band Pass, 40 M only - Center Frequency 7.15 MHz

DXE-RFXL-BPF20M - Band Pass, 20 M only - Center Frequency 14.15 MHz

14

DXE-RFXL-BPF15M - Band Pass, 15 M only - Center Frequency 21.15 MHz

DXE-RFXL-BPF10M - Band Pass, 10 M only - Center Frequency 28.50 MHz

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Lightning

While most amateur radio installations rarely suffer damage from lightning (even though they never
disconnect their equipment); the best protection is to disconnect electrical devices during storms.
The key to proper lightning survival is proper grounding of feedlines and equipment, and
maintaining integrity of shield connections. A proper installation improves lightning protection and
enhances weak-signal receiving performance. The DXE-RLP-75FF Lightning Protector, 75-ohm,
DC Pass, Type F Connectors is one optional device that could be used. Consult lightning protection
and station grounding information in ARRL publications, the National Association of Broadcasters
(NAB) handbook or other reliable sources.

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.

Manual Updates

Every effort is made to supply the latest manual revision with each product. Occasionally a manual
will be updated between the time your DX Engineering product is shipped and when you receive it.
Please check the DX Engineering web site (www.dxengineering.com) for the latest revision manual.

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

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Specifications subject to change without notice.

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