DX Engineering DXE-KEYLINE-DUAL Instructions manual

DX Engineering

Key Line Combiner-Splitter

DXE-KEYLINE-DUAL

DXE-KEYLINE-DUAL-INS Revision 0a

© DX Engineering 2021

1200 Southeast Ave - Tallmadge, OH 44278 USA

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

Fax: [phone] ∙ E-mail: [e-mail]

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Introduction

The DX Engineering Key Combiner-Splitter – DXE-KEYLINE-DUAL can take two ground-on­transmit amplifier keying lines from up to two transceivers or other devices and connect them to
two amplifiers or accessories when used with (customer supplied) coaxial switches.

Some hams have two radios and two amplifiers or an amp and an accessory that both need to be
keyed. While a couple of coax switches can handle the RF, now the DXE-KEYLINE-DUAL
handles the PTT keying from two radios going to two amplifiers or to one amp and one accessory.

This device is handy when using Amateur Radio devices that need to “share” a T/R keying line and

don’t have a keying line pass-through. Each keying input or output is guarded with a separate 45V 2A

Schottky diode, providing ground-on-transmit isolation between each accessory keying line. The unit
keeps the load or voltage of any one piece of equipment from affecting the others. The voltage and
current handling depends upon the rating of the transceiver(s) transistor or relay amplifier keying
circuit. Check your transceiver manual for the total voltage and current that it will safely handle. This
device handles keying lines only. Other connections and appropriate amplifier and accessory
operation must be considered. This device is passive, meaning that it requires no power to function.
It is not a transistor buffer and it has no relays. All four connectors on the DXE-KEYLINE-DUAL
are female RCA phono.

In one example, using the DXE-KEYLINE-DUAL with two coaxial cable switches, you can
choose:

Transceiver 1 with amplifier 1
Transceiver 2 with amplifier 2
Transceiver 1 with amplifier 2
Transceiver 2 with amplifier 1

Features

 Works with most transceivers using ground-on-transmit keying
 Allow one of two transceivers to send the transmit key line to one of two amplifiers
 Center Positive Keying
 Schottky diode protection between outputs
 Common RCA Phono connections
 Unit is passive - does not require power to operate

Manual Updates and Information

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.

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The PTT INPUT(s) are connected to the transceiver’s SEND LINE connections. The DXE-
KEYLINE-DUAL depends upon the voltage and current rating of your transceiver's transistor or
relay amplifier keying circuit, so refer to your transceiver manual for the total that it will safely
handle. Most accessory keying lines float at 13.8 Vdc at only a few milliamps during operation
when sinked to ground, so this combination typically works without issue.

The PTT OUT1 is connected to amplifier #1 KEY LINE.
The PTT OUT2 is connected to amplifier #2 KEY LINE.

The PTT INPUT(s) are connected to the transceiver’s amplifier keying line connection, labeled as
‘SEND,’ ‘Relay’ or ‘TX GND.’ For some transceivers, a special DIN, mini-DIN or other connector
cable assembly may be required.

Two (customer supplied) Coaxial cable switches are used to route the RF from the transceivers to
the amplifiers as desired.

All connections on the DXE-KEYLINE-DUAL use standard RCA phono connectors.

Typical Wiring Diagram

NOTE: ‘KEY LINE’ in the above diagram is also known as:

for Acom ‘KEY IN,’ or for Ameritron ‘Relay’ and ‘PTT’.

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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 2021

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Specifications subject to change without notice.