LDG ALK-2 Operation Manual

ALK-2 OPERATIONS MANUAL MANUAL REV A

LDG ALK-2 Two-Port

Audio/Linear/Key

Switch

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LDG Electronics

1445 Parran Road

St. Leonard MD 20685-2903 USA

Phone: [phone]

Fax: [phone]

[e-mail]

www.ldgelectronics.com

Table of Contents

Introduction 3
Jumpstart, or “Real hams don’t read manuals!” 3
Specifications 3
Important Safety Warning 4
Getting to know your ALK-2 4

Front Panel 4
Rear Panel 5
Pinouts 5

Block Diagram 6
Installation 7
Operation 7

Desktop / Local Operation 7
Remote Operation 7

Application Information 7

Examples 7

Technical Support 8
Two-Year Transferrable Warranty 8
Out Of Warranty Service 8
Returning Your Product For Service 9
Product Feedback 9

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INTRODUCTION

LDG pioneered the automatic, wide-range switched-L tuner in 1995. From its laboratories in St.
Leonard, Maryland, LDG continues to define the state of the art in this field with innovative
automatic tuners and related products for every amateur need.

Congratulations on selecting the LDG ALK-2 two-port Audio/Linear/Key switch. The ALK-2
is a versatile product, electronically switching a common 1/8” stereo jack and stereo RCA jacks
between two other sets of 1/8” stereo/RCA jacks. Although the intended purpose of the ALK-2 is
to switch stereo audio, code keys, or linear amplifier interface signals; virtually any pair of low
voltage signals can be switched between the two ports.

JUMPSTART, OR “REAL HAMS DON’T READ MANUALS!”

Ok, but at least read this one section before operating the ALK-2:

1. Connect a 1/8” stereo plug or a pair of RCA plugs to the common port, and a 1/8” stereo plug

or pair of RCA plugs to each of the two switched ports. These can be any cables with 1/8”

stereo plugs or RCA plugs installed, such as computer speakers, home stereo audio, iambic

paddles, straight keys, linear amplifier control cables, headphone audio, etc.

2. Connect at 12 volt power supply capable of supplying 100 mA to the 2.5 x 5.5 mm coaxial

power jack (center positive)

3. Press the front panel button to toggle between which switched set of jacks is connected to the

common set of jacks. The front panels LEDs indicate which port is active.

4. When a port is selected, both the 1/8” stereo jack and the two RCA jacks of that port are

connected to the common port.

5. The ALK-2 1/8” stereo plug on each port is wired in parallel with the two RCA jacks on that

port. This allows one to; for example, plug a 1/8” stereo plug into the common port, but use

RCA plugs on the switched ports, or vice versa, or any combination thereof.

SPECIFICATIONS

Two switched sets of parallel-connected 1/8” stereo jacks and RCA jacks.

•

Two circuits (stereo) switched. Red jacks are right channel, white jacks are left channel.

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Stereo 1/8” plug and RCA plugs of a given port are wired in parallel

•

Maximum current 1A per circuit, 32 V.

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Remote operation possible (see Application Hints)

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Requires 12 volts at 100 mA, 2.5 x 5.5 mm jack, center positive

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If RF is transmitted through the ALK-2, keep it below 5 watts, 30 MHz, 3:1 SWR.

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