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The Elecraft KX3 and One Amateur’s Weekend Project:
A Guide to KX3 Mobile Installation and Operation
Matt Zilmer, W6NIA
23 November, 2012 ‐ Rev B1 (1.6)
Introduction
There can be no doubt that the KX3 is a revolutionary Amateur transceiver. Its technical specs, compact
size, light weight, and general versatility perfectly match the requirements of a portable, mobile, or fixed
station rig. This Guide is written to assist those interested in the KX3’s mobile installation and operation.
Essential factors in mobile operation are significantly different than when operating portable or at a
fixed station. In many ways, operation of any HF transceiver in a mobile setting is non‐optimal. Simply
put, this means that a series of compromises play out for mobile use, including both the installation and
operation of the transceiver.
One aspect of KX3 mobile installation and operation that is emphasized in this Guide is safety. No
mobile installation should detract from it, so safety is treated herein as a serious issue with specific
recommendations that will assist the installer and Amateur operator in maintaining passenger and
driver safety.
Topics in this Guide include the following:
‐ Scope and Warnings
‐ Safety and Legal Considerations
‐ Location and Mounting
‐ Powering the KX3 and KXPA100
‐ Cabling Like a Pro
‐ Speaker Output
‐ Antenna Installation
‐ Operating Tips
‐ Updates To This Guide and In Closing
Scope and Warnings
Scope Note: This Guide’s scope covers only installations in vehicles that have negative ground electrical
systems. If your vehicle has a positive ground system, consult your dealer’s and/or Elecraft’s technical
staff for advice on power considerations for the KX3 and KXPA100.
Warning Note: Some hybrid vehicles don’t use 12 volts for their starting batteries. If your hybrid is in
this category, don’t even think
about using its battery to power your KX3 or KXPA100. In many hybrids
an inverter‐based DC to DC converter is used to power the 12V accessories (radio, fans, illumination, etc.)
and any in‐vehicle power sockets. Inverter‐supplied power is usually very noisy, and shouldn’t be used for
the KX3. If in doubt, check your 12V accessory power with an oscilloscope. DC power should meet
Elecraft’s DC power quality specifications. If it doesn’t you may want to add conditioning and filtering
circuits to clean up the DC supply.
