MGL Avionics Stratomaster Maxi Singles GPS-1 User manual

Stratomaster Maxi Single
GPS-1
GPS Navigation System
The GPS-1 is a powerful 16 channel GPS navigation system. It is a panel mount GPS which
easily fits into a standard 3.5” cutout. The GPS-1 boasts most of the features only found in
high end GPS navigation equipment.
Features amongst others include:
•Panel mount 3.5” standard aviation footprint
•16 Channel highly sensitive GPS receiver
•WAAS (Wide Area Augmentation System) compatible
•20 user defined routes
•150 user defined waypoints
•Quick and easy to create and manage waypoints and routes
•Quick to find the nearest waypoint to the current position
•5 navigation and information displays
•Sunrise/Sunset calculator
•NMEA output to interface to other GPS based instrumentation
•TTFF (Time to First Fix) within 45 seconds
•Graphic LCD display with adjustable contrast
•Large non-reflective ultra high impact acrylic lens with rear backlight
•Active antenna for even higher sensitivity
•3.5” standard ABS enclosure
•Low power consumption
•PC interface to manage waypoints and routes
•CD included with various GPS applications

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GPS Introduction
The GPS System was originally developed by the U.S. Department of Defense where the
primary use was to provide accurate position data for military applications.
This system consists of a constellation of 24 satellites which orbit the earth twice a day. Each
satellite accurately transmits its position and time data. All GPS satellites are synchronized so
that these repeating signals are transmitted at the same instant. The GPS receiver receives
these signals at slightly different times based on where the location of the satellite is. By using
this information the receiver can work out exactly its position from the satellites and can
achieve a position fix on the earth’s surface to within 1m.
Note: Please be aware that the GPS-1 is for VFR only. Please make sure that you
understand the instrument thoroughly before using it for navigation purposes
The GPS-1 and WAAS (Wide Area Augmentation System)
The GPS-1 also supports WAAS. WAAS is a FAA funded project to improve the accuracy of
GPS receivers. There are 2 satellites in a geo-stationary orbit currently over North America
providing additional correction data. The GPS-1 receives these additional signals to make a
more accurate computation of position. Please see http:gps.faa.gov for more information.
Key Assignment
Minus Key
Normal Operation: This key is
used to go back one waypoint
within a route when a route is
selected.
Menu Operation:
This key is used to go up
through the menu system or to
decrement a value.
Screen Select Key
Normal Operation:
Press this key to
toggle between the
various operating and
navigation screens.
Menu Operation:
Used to cancel or exit
the current menu.
Mark Waypoint
Normal Operation:
Press this key to mark the
current position as a new
waypoint.
Menu Operation:
No function
Goto
/
Nearest Waypoint
Normal Operation:
Press this key once to select
a waypoint to navigate to.
Press it twice to show the
nearest waypoint to the
current position.
Menu Operation:
No Function
Ente
r
/
Route Key
Normal Operation:
This key is used to select a
route for navigation.
Menu Operation:
This key serves as an enter key.
Plus Key
Normal Operation:
This key is used to go forward one
waypoint within a route when a route is
selected.
Menu Operation:
This key is used to go down through the
menu system or to increment a value.

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Operating Screens
The GPS-1 has 6 individual display screens. There are 3 information screens, 2 navigation
screens and 1 menu system screen.
Satellite Signal Screen (Information Screen)
This screen shows information such as the number of
satellites used in the fix data, the fix type, the satellite PRN
(ID) number as well as the carrier to noise signal strength in
dbHz.
SkyView Screen (Information Screen)
This screen shows information such as the horizontal/vertical
accuracies, PDOP (position dilution of precision) and satellite
position relative to the current position and the fix type.
GPS Information Screen
This screen is useful to display position data when no route or
waypoint has been selected. It displays information such as a
bearing tape, altitude, ground speed and latitude and
longitude as well as time.
Primary Navigation Screen
This screen is your primary navigation screen when a route or
waypoint has been selected. Information such as waypoint
name, current heading, ground speed, distance to waypoint,
ETE (Estimate Time Enroute), as well as an arrow indicating
your direction to the selected waypoint is displayed.
Secondary Navigation Screen
This screen is your secondary navigation screen displaying
information such as waypoint name, current heading,
distance to waypoint, current ground speed, ETE (Estimate
Time Enroute), as well as your track and a CDI (Course
Deviation Indicator).
Menu System

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Satellite Signal Screen
This screen shows the satellites carrier to noise ratio (Signal strength), PRN (ID) number as
well as how many satellites are used in the fix data.
The bars height represents the carrier to noise ratio in dbHz (Signal Strength). This value can
vary from 0 to 60 dbHz.
Skyview Information Screen
This screen is useful to determine the satellites orientation in relation to the GPS-1.
Horizon
Position fix type
HDOP Value (2D Fix) or
PDOP Value (3D Fix).
North Indicator
45 Degrees above
Horizon
Vertical Accuracy
in meters
Horizontal Accuracy
in meters
Satellite PRN Number and position
Directly Overhead
Fix type
The number of
satellites used in the
p
osition data. Shaded bars indicate that the
GPS-1 is still negotiating with
the satellite and this satellites
data is not yet being used for
a position fix.
Satellite PRN (ID) number
Solid bars indicate that
this satellite is currently
been used for the fix
data.

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Description of items:
North Indicator: This is the direction of true north.
Horizon, 45 Degrees above horizon and directly overhead: These 3 rings show the
elevation of the satellite from the horizon (outer ring).
Horizontal Accuracy (HACC): This is a value expressed in meters (m) indicating what the
horizontal accuracy is of the position fix.
Vertical Accuracy (VACC): This is a value expressed in meters (m) indicating what the
vertical accuracy is of the position fix.
HDOP Value: This is a unit less value representing the horizontal precision of dilution. A
value of 1 indicates optimum satellite constellation and high-quality data. This value is shown
when the GPS-1 does not have a 3D Fix.
PDOP Value: This is a unit less value representing the position precision of dilution which is a
combination on the horizontal precision of dilution (HDOP) and the vertical precision of
dilution (VDOP). A value of 1 indicates an optimum satellite constellation and high-data
quality. This value is shown when a 3D fix is achieved. PDOP values in excess of 8 are
considered poor.
Note: A position fix with a PDOP of 30 could be as much as 150m from its true location.
Satellites that are dispersed throughout the sky will achieve low PDOP values while satellites
that are in a straight line will achieve a high PDOP value.
Position Fix Type: This can vary from “Acquiring” (When the GPS-1 is trying to obtain
position fix data) to a 2D Fix (No altitude data is valid) to a 3D Fix (Altitude data is valid).
Satellite PRN Number and Position: The PRN (Pseudo-Random Number) number is the
satellites ID number and the position within the circles is a function of the satellites elevation
and azimuth.
GPS Information Screen
This screen is useful to display when no route or waypoint has been selected. It displays
information such as a bearing tape, altitude, ground speed and latitude and longitude as well
as time.
Heading Magnifier
Moving Heading
Tape
This field toggles between
Time & Date and a latitude
/longitude readout. This field
toggles at 5 second
intervals.
Current ground speed.
Units configurable under
the setup section in the
menu system.
Altitude Readout. The
altitude units can be
changed under the
setup section in the
menu system.

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Primary Navigation Screen
This screen is your primary navigation screen when a route or waypoint has been selected.
Information such as waypoint name, current heading, ground speed, distance to waypoint,
ETE (Estimate Time Enroute), as well as an arrow indicating the direction to your desired
destination is displayed. Note: This screen will be automatically shown when the GPS-1 has
a 2D or 3D fix.
Secondary Navigation Screen
This screen is your secondary navigation screen displaying information such as waypoint
name, current heading, distance to waypoint, current ground speed, ETE (Estimate Time
Enroute), as well as your track and a CDI (Course Deviation Indicator).
Waypoint Descriptor
Fix Indicator
2D: 2D Fix has been achieved
3D: 3D Fix has been achieved
AQ: Acquiring a fix
Current Heading
True/Magnetic North
Indicator
Distance
remaining to
selected waypoint ETE (Estimated Time
Enroute) based on
current ground speed
Direction to waypoint pointer Graphical heading display
CDI (Course Deviation
Indicator
Waypoint Descriptor Fix Indicator
2D: 2D Fix has been achieved
3D: 3D Fix has been achieved
AQ: Acquiring a fix
Distance remaining to
selected waypoint Graphical heading display
ETE (Estimated Time
Enroute) based on
current ground speed
Ground Speed
Ground Speed
Current Heading
Track to Waypoint

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The Menu System
Waypoint Setup
This menu allows the user to create and manage their
waypoint database.
Note: The GPS-1 can store up to 150 waypoints.
New Waypoint
The user can create a new waypoint by entering a unique
identifier up to 10 characters long. By default the latitude and
longitude is the current position. The distance and track is
referenced to the current position.
Move the highlight over ***save*** and press to save
once you have finished entering a waypoint name and latitude
and longitude. Press to cancel and return to the waypoint
menu.
Delete Waypoint
Select “Delete Waypoint” to delete a waypoint.
Use the and keys to highlight the waypoint that must
be deleted. Press over the desired waypoint to be
deleted.
Note: The waypoint will also be deleted out of the route
memory if it is assigned to a route.

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View Waypoint
Select “View Waypoint” to view a waypoint.
Use the and keys to highlight the waypoint that you
want to view. Press to view it. The distance and track is
referenced to the current position.
Edit Waypoint
Select “Edit Waypoint” to edit a waypoint.
Use the and keys to highlight the waypoint that you
want to edit. Press to edit the waypoint.
Move the highlight over ***save*** and press to save
once you have finished editing the waypoint name and
latitude and longitude. Press to cancel and return to the
waypoint menu. The distance and track is referenced to the
current position.
Delete All
Note: Use this with caution. All waypoints and routes in the
GPS-1 memory will be deleted.
Press to delete all waypoints and route information.
Press to cancel and return to the waypoint menu.

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Waypoint Alert
The GPS-1 will notify the user when he is approaching the
selected waypoint. Use the and keys to adjust the
distance to the waypoint when the message alert must
appear.
Marking a Waypoint
Use the key during the normal operation to mark a
waypoint. The mark waypoint menu will appear. This allows
the user to enter a unique waypoint name up to 10 characters
long and also allows the user to change the latitude and
longitude if desired. The waypoint name will default to the
next available number and the latitude and longitude will
default to the present position on entering the function. The
distance and track is relative to your current position.
Goto a Waypoint
Press the key once during normal operation to go to a
predefined waypoint. The goto waypoint menu will appear.
This will display all pre-stored waypoints. Use the and
keys to scroll up and down and press to select a
waypoint.
Note: Any pre-selected route or waypoint will be ignored and
the new selected waypoint will be used for navigation.
Finding the nearest waypoint
Press the key twice to display the nearest waypoint to
the current position. The distance and track to the nearest
waypoint is also shown.
Arriving at a Waypoint
The arriving message box will be displayed if the distance to
the selected waypoint is less then the waypoint alert value.
Press the key to acknowledge the message.
Note: The arriving at a waypoint message box will only
appear when either of the navigation displays is shown.

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Waypoint Messages
This message box will appear when an operation on a
waypoint is performed and there are no waypoints stored in
the waypoint memory.
Route Setup
New Route
The user can create a new route by entering a unique
identifier up to 10 characters long. A route can contain upto
30 waypoints.
Move the highlight over ***save*** and press to save
once you have finished entering a route name and latitude
and longitude. Press to cancel and return to the route
menu.
Add/Insert Waypoint
Select “Add/Ins Waypoint” to add or insert a waypoint into a
route.
Select a route to add/insert a waypoint into.
Use the and keys to select where to insert the
waypoint into. Press to insert the waypoint into the route.

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Remove Waypoint
Select “Remove Waypoint” to remove a waypoint from a
route.
Select the route the waypoint is in.
Use the and keys to highlight which waypoint is to be
deleted. Press to delete the waypoint from the route.
View Route
Select “View Route” to view a route.
Use the and keys to select the route to view. Press
to view the route.
Use the and keys to view the waypoint in more
detail.
The distance and track is referenced to the current position.

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Edit Route Name
Select “Edit Route Name” to change the route name.
Use the and keys to select the route name to edit.
Press to select.
Once finished editing the route name, move the highlight over
***save*** and press .
Delete Route
Select “Delete Route” to delete a route from the route
memory.
Use the and keys to select the route to be deleted.
Press to select.
Note: If all the waypoints are deleted, all the routes will be
deleted automatically.
Starting a route
Press during the normal operation to select a route to navigate along.
Use the and keys to select the route to start
navigating along. Press to select.
Note: The route can either be followed in the forward or
reverse direction.
Use the and keys to select which direction to follow
the route.

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The route selected message box will appear.
Route Messages
This message box will appear when an operation on a route is
performed and there are no routes defined in the route
memory.
Sunrise/Sunset Calculator
This sunrise/sunset calculator uses a unique algorithm based
on date and position to accurately determine the sunrise and
sunset times. This feature can be useful to maximize your
flying time.
Contrast
Use the and keys to adjust the contrast.
Backlight
Use the key to turn the backlight on or off.

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Setup Menu
Select this menu to change various options such as North Reference, Magnetic Variation,
position format, Distance/Altitude units, UTC (Universal Time Coordinate) offset and CDI
(Course Deviation Indicator) Scaling .
North Reference
This option allows the user to change all Bearing/Heading
related data to reference either to True or Magnetic North.
Magnetic North is what a compass needle points to. True
North is the direction from your current position to the North
Pole.
Magnetic Variation
This is the angle between Magnetic and True North. Magnetic variation varies both from place
to place, and with the passage of time.
This option is used in conjunction with the North Reference
set to magnetic.
Position Format
The GPS-1 can be setup to display all position data as
degrees, minutes and seconds (d-m-s.s) or as decimal
degrees (d-m.mmm). Use the key to toggle this option.
Distance Units
All distance/speed related data can be shown in either metric
(km/kph), statute (sm/mph) or nautical (nm/kts). Use the
key to toggle this option.
Altitude Unit
The altitude can be expressed either in meters or feet. Use
the key to toggle this option.

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UTC (Universal Time Coordinate) Offset
This option allows the user to change the UTC offset. Use the
and keys to increment and decrement the time in 10
minute steps.
CDI (Course Deviation Indicator) Scale
Use this function to adjust the CDI scale to either 1, 2 or 5.
Use the key to toggle this option.
GPS Fix Data
The GPS-1 will display a message box when trying to acquire
a position fix. Once a 2D or 3D fix is achieved the message
box will disappear.
Obtaining a fix
Depending on the receiver’s knowledge of last position, current time and ephemeris data, the
GPS-1 will apply different strategies to startup.
Coldstart
In coldstart the GPS receiver has no knowledge of the last position or time. This is the case
when no almanac or ephemeris data is available.
Warmstart
A warmstart is performed when the receiver has access to a valid almanac data and has not
significantly moved since the last position has been taken. This is typically the case if the
receiver has been shut down for more then 2 hours, but still has knowledge of its last position,
time and almanac. However, because the ephemeris data is invalid, the receiver needs to
wait till it has received this data.
Hotstart
A hotstart is performed when the receiver still has access to valid ephemeris data and precise
time. The receiver can predict the currently visible satellites and therefore a position can be
calculated quicker.

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NMEA Output
The GPS-1 supports the output of standard NMEA 0183 version 2.3 (compatible with 3.0)
data using the auxiliary serial port on the rear DB9 connector. The settings are 9600 baud, 8
data bits and 1 stop bit. The outputting of this data can be useful when other avionic
equipment needs a GPS data input.
Pinout
DB9 Pin 6 -> NMEA RXD
DB9 Pin 7 -> NMEA TXD
DB9 PIN 5 -> Ground
The following NMEA sentences will be outputted:
•GGA - Global positioning system fix data
•RMC – Recommended minimum specific GNSS data
•GSA – GNSS DOP and active satellites
•GSV – GNSS satellites in view
•GLL – Geographic position (Latitude/Longitude)
•VTG – Course over ground and ground speed
•ZDA – Time and Date
•GRS – GNSS range residuals
•GST – GNSS pseudo range error statistics
NMEA stands for the National Marine Electronics Association. For more information please
visit www.nmea.org.
GPS Antenna’s
Even the best GPS receiver in the world will become useless unless a proper antenna is
chosen. The GPS-1 supports active antennas only. An active antenna contains the radiating
element as well as a LNA (Low noise amplifier). Additional active antennas can be purchased
from MGL Avionics if your antenna is rendered faulty. The GPS antenna is terminated in an
mmcx connector.
Built in Antenna Supervisor
A built in antenna supervisor is standard on the GPS-1. A message box will appear indicating
the status of the antenna.
Screen shots of the various antenna status messages
Short Circuit Message
Please attach an antenna to the unit, and then cycle the
power.
Note: The GPS-1 turns the power to the antenna off to avoid
damage to the internal antenna circuitry, therefore power to
the unit needs to be cycled.

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Open Circuit Message
The message will disappear as soon as an antenna is
attached to the unit.
Initialising Antenna Message
The GPS-1 is busy initializing the antenna. This message will
disappear as soon as this initialization has been completed.
Antenna Problem
Please check the antenna and rear antenna connector for
possible damage.
Antenna Placement
As stated previously, the world’s best GPS receiver can be rendered useless unless a correct
antenna is chosen and the correct placement of the antenna is achieved.
Note: The GPS antenna must be positioned such that it always has a full view of the sky, and
no metal objects are blocking its view.
Please see the connection diagram on the last page to see where to connect the GPS
antenna.
Resetting the GPS-1 to factory defaults
Press the and keys when applying power to the unit to reset the unit to the factory
default settings. Caution: All waypoint and route information will be lost.
Firmware Upgrades
Please check our website for the latest firmware. The GPS-1 firmware can be upgraded by
running the GPS-1 upgrade program and connecting the GPS-1 to the PC via a serial cable.
PC Connectivity
The GPS-1 can be connected to a PC to allow the user to manage their waypoints and
routes. There are various PC programs supplied on the accompanied CD to do this. It is
recommended that the user evaluate these programs and select the one that best suites his
requirements. The communication settings is set as 9600,8,N,1
Please note: The GPS-1 is made to emulate a Magellan GPS Tracker. This allows the user
to use a wider range of GPS application programs. Please be aware that the Magellan GPS

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Tracker only uses 6 characters for the waypoint name. When uploading these points to a PC
any waypoint names that are longer then 6 characters will be truncated. Please be aware that
various GPS applications have slight differences when managing waypoints and routes. It is
recommended that the user has fully tested these programs before navigating with the GPS-
1.
Pinout
DB9 Pin 2 -> GPS TXD
DB9 Pin 3 -> GPS RXD
DB9 Pin 5 -> Ground
GPS Terminology
2D Fix: When 3 satellites are obtained, the GPS can determine a latitude/longitude position
fix.
3D Fix: When 4 or more satellites are obtained, the GPS can determine a latitude/longitude
as well as altitude fix.
UTC Offset: (Universal Time Coordinate). UTC was formally known as GMT (Greenwich
Mean Time) but changed in 1986. This is difference in time between local and UTC time.
NMEA: NMEA stands for the National Marine Electronics Association. See www.nmea.org
PRN: (Pseudo- Random Number). This is the satellites identification number.
ETE: (Estimated Time Enroute). This is how long it will take to reach your destination
traveling at the current speed.
WAAS: WAAS is a FAA funded project to improve the accuracy of GPS receivers. There are
2 satellites in a geo stationary orbit currently over North America providing additional
correction data. The GPS receives uses these additional signals to make a more accurate
computation of position. See http:gps.faa.gov
HDOP: (Horizontal Dilution of Precision)
PDOP: (Precision Dillution of Precision)
Azimuth: This is the direction of a celestial object, measured clockwise around the observer's
horizon from north.
Technical specifications:
Display temperature range (operational): -20 to +80 degrees C
Supply voltage: +8 to +18V. +24/28V with optional pre regulator
Supply current: 80mA with active antenna
GPS Receiver: Self contained 16 channel receiver
Update rate: Once per second
Antenna support: active antennas only
Antenna connector: mmcx connector
Keypad: 6 button tactile feedback
Protective lens: non-reflective ultra high impact acrylic
Backlight: on or off (Green LED)
Contrast: Variable
Weight: 190 grams

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Warranty:
MGL Avionics warrants their products for a period of one year from date of purchase against
faulty workmanship. Warranty is limited to the replacement of faulty components and includes
the cost of labor. Shipping costs are for the account of the purchaser.
Note for operation on supplies with inductive loads:
Any operation of electronic instrumentation on power supplies that are subject to high
voltages caused by operation of inductive loads (starter motors, solenoids, relays) are
required to be fitted with suitable protection.
All Maxi Singles are guaranteed to withstand temporary over voltage up to 40V without
additional protection. We recommend that measures are taken to prevent voltage transients in
excess of this limit.
MGL Avionics recommends the fitment of a fuse in line with a 33V transorb (available from
MGL Avionics) to protect electronic instruments, radios and intercom systems. Only one such
arrangement is required for a cluster of instruments.
Please note that product warranty excludes damages caused by unprotected, unsuitable or
incorrectly wired electrical supplies.
Installing the GPS-1
The drawing on the following page shows the connections required to operate the GPS-1.
Power supply here assumes a 12V DC source. It is recommended to install suitable
protection against over voltage such as can be generated by solenoids and starter motors.
RED
BLACK
Fuse
Power
switch
Positive supply
(+12V from battery)
Negative supply
(airframe ground)
Suggested fuse rating:
1.0 A slow blow
To other instruments
Cannon D-9
connector
D-9 Connections
Pin 1----- Red ------------- Positive Supply pin 1
Pin 5----- Black ------------ Negative Supply pin 5
Pin 2----- GPS TXD
Pin 3----- GPS RXD
Pin 6----- NMEA RXD
Pin 7----- NMEA TXD
GPS-1
Global Positioning
System
GPS Antenna

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