Micom GPS Receiver User Manual

Using the MICOM GPS Receiver

Table of Contents

Introduction................................................................................................................... 1

GPS Receiver Functions ................................................................................................. 2

Format of GPS Information........................................................................................ 2

How to Get the Best Results from your MICOM GPS Receiver .................................. 2

GPS Antenna ................................................................................................................. 3

Antenna Description ................................................................................................. 3

Selecting a Proper Location for the GPS Antenna ...................................................... 3

Installing the GPS Antenna ........................................................................................ 3

Operating the GPS Receiver........................................................................................... 4

GPS Menu ................................................................................................................ 4

First-Time Operation................................................................................................. 5

Operating Instructions............................................................................................... 5

Sending Your Position/GPS Position Requests ............................................................ 6

What to do if …........................................................................................................ 7

Introduction

This Supplement to the “MICOM-2E/2R ALE HF-SSB Transceiver Owner’s Guide”, Publication
68P02952C60-A, provides you with information on the GPS receiver, an option for the new versions
(Version CK) of the MICOM-2E/2RS/2TS ALE HF-SSB transceivers models which is not documented in
the Owner’s Guide.

Note

The information appearing in this Supplement is intended for use with the following publications:

• Owner’s Guide, MICOM-2E/2RS/2TS ALE HF-SSB Transceivers, Publication 68P02952C60-A.

• Supplement to Owner’s Guide, MICOM-2ES/2RS/2TS ALE HF-SSB Transceivers, Publication

6886872J01.

MICOM transceivers equipped with an internal GPS receiver have a connector for
the GPS antenna on their rear cover.

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GPS Receiver Functions

The GPS receiver is an integral part of the MICOM transceiver and can be used whenever the GPS
antenna supplied together with the MICOM transceiver is properly connected and installed.

The GPS receiver provides accurate time and navigation data. The navigation data includes the
geographical coordinates (position data) and the altitude. When the MICOM transceiver is moving,
you can also see the speed and direction (heading).

The information collected by the GPS receiver can be displayed on the MICOM display when using
the CH and FREQ modes. In the ALE mode, the position data can be reported by means of AMD
messages; it can also be automatically reported in response to position queries (also sent by AMD
messages).

Format of GPS Information

The format of the navigation data can be selected in accordance with your needs:

• LLA format: Latitude, longitude and altitude (LLA). The latitude and longitude are displayed in
degrees, with a precision of hundredths of arc minutes (1/100 min); the altitude is reported in
meters, relative to the mean sea level (MSL).

Velocity is reported as the change in the East, North, and Up coordinates, presented in
meter/sec with a precision of 0.001 m/sec.

• ECEF format: Earth-Centered, Earth-Fixed format for position and velocity. Provides your
position and velocity in a Cartesian (X, Y, Z) coordinate frame with its center at the Earth's
center, the Z-axis through the North Pole, and the X-axis through 0 degrees longitude, 0
degrees latitude. The position is reported in meters.

Velocity for each axis (that is, is the change in the X, Y and Z coordinate) is displayed in
meter/sec, with a precision up to 0.001 m/sec.

The time is always presented on basis of the UTC (Universal Time Coordinated).

How to Get the Best Results from your MICOM GPS Receiver

The GPS receiver extracts the information it needs by analyzing the signals received from GPS
satellites. These satellite periodically transmit navigation messages, where the transmission of each
complete message requires almost 15 minutes. To calculate all the data your GPS receiver is capable
of providing, it must receive and decode navigation messages from at least 4 GPS satellites (the GPS
receiver can use as many as 8 satellites to improve accuracy).

Therefore, after turning a GPS receiver on for the first time after a long period of inactivity, it is
essential to let the GPS receiver operate continuously for at least 15 minutes, to enable it to collect
updated almanac data. After this initial 15-minute interval, a GPS receiver can relatively rapidly
acquire the satellites and calculate its position; thereafter, a GPS receiver must remain on only for a
few minutes in order to be able to provide navigation data.

The internal GPS receiver is always powered when the transceiver is turned on. Therefore, if the GPS
antenna is connected, the GPS receiver can start the acquisition process as soon as the transceiver is
turned on, and can then track the satellites continuously. Turning the MICOM transceiver off will
force the GPS receiver to reacquire the satellites.

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GPS Antenna

Antenna Description

The GPS antenna is a compact active omnidirectional antenna with magnetic
mounting, which attaches easily and firmly to vehicle’s steel body parts, even
when painted. The antenna will not attach to non-magnetic alloys (e.g.,
aluminum alloys), nor to parts made of composite materials (e.g., fiberglass).

The antenna connects to the GPS connector of the MICOM transceiver through a 5-meter (15 feet)
long coaxial cable, which is part of the antenna. This cable carries both DC power for the antenna,
and the received GPS signals.

The antenna is 42 mm wide by 50.5 mm long by 13.8 mm high (1.65”×1.99”×0.55”), and it requires
a minimal ground plane of 60 by 60 mm (2.36”×2.36”) to provide the specified performance.

Selecting a Proper Location for the GPS Antenna

GPS satellites transmit their special signals in the 1575 MHz range: such signals do not penetrate
conductive or opaque surfaces. When selecting the location of the GPS antenna, you should also be
aware that strong local interference as well as reflections from nearby objects may disrupt normal
reception and degrade the signal quality.

Thus, GPS antennas should be installed on horizontal surfaces, in a place that provides a clear view of
the sky, which, in as far as possible, is not obstructed by large objects. For example, the roof of the
passenger’s cabin is a good place for the GPS antenna.

Moreover, you should not park the vehicle under dense foliage or other cover, for example, in a
garage, if you want to get a position fix from your GPS receiver.

Note

When the GPS antenna is installed on a metal surface for prolonged periods, care
must be taken to insulate the antenna, to prevent galvanic corrosion.

Installing the GPS Antenna

Before starting, select a good location for the GPS antenna and plan the route for the cable
connecting it to your transceiver. The cable route should be selected in the same way you would
select the route for antenna cables: however, never run the GPS antenna cable in parallel to the
transceiver’s cables!

GPS Antenna

Connector

Figure 1. Location of GPS Antenna Connector on the MICOM

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