User Manual for the Seagull Glide Wireless Dashboard Telemetry System and Recorder
Patent Pending
Document Version 3.1
Please read this manual before using your new system.
Thank you for your purchase! This instruction manual will guide you through the installation and operation of
your Seagull Glide Wireless Dashboard Telemetry System.
The Glide System is the first instrument designed for models that supports electronic Total Energy Compensation
(derived from airspeed), and that lets you change key variometer parameters while your model is in flight! Many
other features are provided with the Glide System, making it an incredibly versatile all-in-one instrument.
Please read the entire manual carefully before proceeding. If, after you read the manual (including the
Troubleshooting sections!) you have further questions or problems, please visit our web support page for additional
support options, at http://www.eagletreesystems.com/Support/support.html. Note that the latest version of this
manual is available in PDF form from the Support page of our website.
Intended Uses
The Seagull Glide System is designed to be used to transmit data in Radio Controlled model Gliders, or on other models where high
resolution altitude and airspeed measurement and variometer features are needed.
Packing List
Your Seagull Glide System includes the Wireless Telemetry Data Dashboard Receiver, the Wireless Telemetry transmitter, Flight
Data Recorder, approximately 3 feet (1 meter) of Pitot Tube hose, plastic Pitot Tube, battery Y-connector, USB cable, plastic clip for
mounting dashboard to radio antenna, and Windows CD.
If you purchased the Glide Recorder only (GDR-KIT-STD), the Wireless Telemetry Transmitter and Wireless Telemetry Data
Dashboard Receiver are NOT included.
Optional expanders for measuring Temperature, RPM, Servo movements, G-Force, Exhaust Gas Temperature, Electric Motor
Current/Voltage, and other parameters are available from Eagle Tree Systems. An External Hookup Kit is also available if you want
to download data from your model without removing the wing.
Steps to Follow
This manual is divided into two sections, Basic and Advanced. The Basic section describes minimal installation and setup of the
Glide unit. These steps do not require a computer. The Advanced section describes other features and options available, and does
require a computer.
NOTE: It is recommended that the basic installation be attempted first to verify system operation, before connecting the device to a
computer in the advanced section.
Installation and use of your Seagull Glide system will be quite easy and enjoyable if you follow these few steps:
1. Read through the manual to understand the warnings, determine the installation and setup sequence, etc.
2. Install the system as described in the Basic setup instructions below.
3. If desired, configure the Seagull system with your PC, as described the Advanced setup instructions below.
4. Bench and range test your model, and have fun!
Your Seagull Glide system has been pre-configured for the following options: Variometer, Airspeed, Altitude, Climbrate, Receiver
voltage, received packet percentage, and signal strength. Other parameters may be displayed (and alarms programmed) by
connecting the unit to a PC and running the Windows application. See the Advanced section for instructions for reconfiguration.
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Important Warnings
• Make sure you have the right transmitter for your area. You are responsible for determining
whether you may use your transmitter in your country! See the transmitter specifications below for
information on frequency and power output. In general, transmitters marked EU or CE are suitable
for use in Europe, and transmitters marked FCC are suitable for USA operation.
• It is very important that you “Antenna Down” range check your model per your radio
manufacturer’s instructions after installing or reconfiguring any electronic equipment, and generally
before each operation. If you have range issues, see the Troubleshooting section, or email
support@eagletreesystems.com.
• The Seagull system is to be used only as described in the “Intended Uses” section below. Other uses
are not supported, and uses where loss of life or injury may result are expressly forbidden.
• Operating your model requires that you keep your eyes on it and give it your full attention. Looking
at the Seagull LCD display while the model is in operation is strongly discouraged. Use the
programmable audible alarms, or have a buddy look at the display, as necessary.
• The Seagull Transmitter and Dashboard Receiver antennas are very flexible, but use care that you
don’t mount them in such a way that they could cause eye or other bodily contact injury.
Basic Installation and Setup Instructions
This section describes the minimal setup and configuration required to use your system. No computer is required for this section.
Install your Data Acquisition Module (Recorder)
NOTE: The recorder’s label has a handy color coded means of indicating the polarity of the various connectors. The red dots on
the label, which are on only one side of the text corresponding to each input, indicate on which side of the plug the red wire
should go.
Connecting the Airspeed Pitot Tube
WARNING: If you mount the Pitot Tube in such a way that it might induce drag on your model, you need to make sure that
it won’t cause the model to become unstable during flight!
The Recorder uses pressure differential via a Pitot Tube (a piece of small fuel tubing which you will fit with a short piece of plastic
insert, supplied) to measure airspeed, just as full size planes do. The static port of the pitot sensor for the Flight Data Recorder V2 is
located inside the Recorder.
The length of the tube should not have a significant effect on airspeed measurement, so it should be no problem to lengthen or shorten
the supplied tube. Also, replacing the plastic insert with metal or other rigid tubing should not significantly affect airspeed
measurement.
NOTE: It is of course not necessary to use the Pitot Tube with the Recorder if you are not interested in measuring airspeed – the other
functions of the Recorder will work without airspeed readings.
NOTE: Additional Pitot Tube kits are available for purchase on our website.
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Method A: If the airplane’s fuselage is relatively sealed, with no large “ram” air openings in the nose of the plane, you can likely
obtain good readings by just leaving the static airspeed connections unconnected.
Method B: A true static pickup can be created with a piece of brass tube (not included). The diameter of this tube is not critical.
See Figure 1 for details of this method. To create the static pickup, you will need to drill 4 small holes into the side of the tube,
spaced equally around the circumference of the tube. If it is difficult to drill all four holes around the tube in a circle, two of the holes
can be drilled farther forward than the other two. Also, a larger diameter tube can be used to make this easier, if the extra weight can
be accommodated.
These holes should be drilled 1.5” or more from the front of the tube, but should not be too close to the tube mount. The holes
should be approximately 1/32” in diameter, and should be deburred if there are burrs from drilling. Once the holes are drilled, the
front opening of the tube should be plugged with epoxy or other. The static tube is mounted parallel to the direction of travel, near
the pitot tube, as shown in the below figure.
Method C: A static source can be obtained from the side of the fuselage, with the rubber tube (or a short piece cut from the pitot tube)
mounted absolutely flush with the side of the fuselage, so that the mouth of the tube is pointing perpendicular to the direction of plane
travel. The location of the static tube should be chosen so that the least disturbance of air possible occurs.
Altitude Measurement
The Seagull Glide system measures altitude via a sensor inside the unit. Altimeters measure slight pressure differences to determine
elevation. Since these pressure differences are relatively small, it’s important that the airplane’s internal pressure doesn’t vary much
due to propwash or moving through the air. Such variation can occur if the front portion of the plane has an opening that causes air
to compress inside of the plane when air is forced into this opening.
If you get lots of altitude variation at level flight, check to see if there are openings in the front of your plane that allow air to enter
and increase pressure inside the fuselage. If your plane is not airtight or at least sealed well up front, you may have altitude
jumpiness, since the altimeter measures changes in air pressure. If you have this problem and/or want very accurate altitude
measurements, a static source can be obtained as follows:
2. There is a predrilled hole to accommodate an external altitude tube. Look at the back of your recorder cover, and use an x-
acto knife to carefully cut the label around the hole.
3. You can now install an external altimeter tube to the nipple of the altimeter sensor just like you do the pitot tube for airspeed,
using an extra piece of rubber pitot tube, or similar. Choose either option A, B, or C for the static source, as described in the
Airspeed section above. If you have installed a static airspeed tube already, that same static tube can be shared with the
altitude static source, by using an optional ‘T’ fitting, as shown in Figure 1.
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Powering the Glide Recorder
IMPORTANT: If you are using the 1 Watt 900 MHz Transmitter, special care must be given to ensure that the
supplied power remains between 5V and 5.75V. The 1 Watt Transmitter will stop transmitting if powered above 5.75V, and
will reduce power output to 500 mW (when in High Power mode) if the voltage drops below 5V.
The battery harness is the cable with a Futaba style
male connector on one end, and male universal
servo connector on the other end. To power the
system, plug the Futaba end into any one of the
recorder’s servo slots. The universal male end of
the harness can plug into a spare channel of your
receiver, or you can connect a separate battery to
the unit. The battery must be at least 4.5 volts to
power the recorder.
Installing the Seagull Transmitter in your Model
Choose a location in your model to install the transmitter. The transmitter is normally mounted with Velcro or double sided tape.
Ideally, the transmitter will be installed with its antenna and body as far away from your radio receiver (RX) as possible, with the
antenna protruding at right angles with your RX antenna, to reduce the possibility of interference. For example, if you have a model
plane with the receiver mounted horizontally along the plane’s fuselage, mount the Seagull so that the antenna is protruding from the
model vertically, as far forward of the RX antenna as possible. Best reception will be obtained if the Seagull antenna is vertical.
Connecting the Seagull Transmitter to your Data Recorder
Ensure that the Recorder is not powered when connecting the transmitter, and ensure that the red wire of the transmitter
cable corresponds with the red dot on the port label (to the right of the connector). Plug the Seagull Transmitter cable into the
“Expansion” port on your Recorder, as shown in Figure 1. Install the transmitter in the upper row of pins, as shown in the figure.
Using the Seagull Wireless Dashboard
The Seagull Dashboard Receiver (the Dashboard) operates from a standard 9V
battery. The battery installs in the back snap-off compartment of the Dashboard.
Approximately 12-14 hours continuous use is typical with an alkaline battery.
Approximately 3-4 hours of continuous use is typical with the 2.4 GHz and 900
MHz/1 Watt systems. Optionally, any battery of between 5-16 volts can be used to
power the Dashboard. Rechargeable 9V batteries will work, but the run time will be
significantly reduced..
Note: If the Dashboard will be unused for long periods, it is a good idea to remove
the battery.
Note: When removing the battery clip, use your thumb to pop the clip off from the
side without the wires. Pushing on the wire side can break the battery clip or the
wires.
Variometer Function: Your Dashboard contains a sophisticated Variometer, employing electronic Total Energy Compensation,
based on changes in Airspeed. Basic variometers do not support total energy, which means that “stick thermals” are reported by the
variometer if you descend or ascend due to elevator movement. Standard total energy variometers reduce the effects of moving the
elevator by monitoring the pitch of the aircraft, which requires an additional probe to be mounted. The Seagull Glide
system uses the airspeed pitot tube for total energy calculations, requiring no additional tube.
The variometer produces a varying tone, which changes as you ascend or descend at different rates. When ascending, the tone will be
broken, with the tone frequency increasing as the rate of ascent increases. When descending, the tone will be continuous, with the
tone frequency decreasing as your rate of descent increases.
Several parameters of the variometer are adjustable. See the Configuration Menu section below for more information.
The Dashboard includes a small speaker, or a set of standard headphones or ‘earbuds’ can be plugged into the dashboard for noisy
areas. Note that the headphone volume is fixed.
USB Connection: The USB cable supplied with your Recorder connects to the Dashboard at this port. Note that the RED wire of the
USB cable goes up, as shown by the red dot above “USB” on the Dashboard label.
LCD Display: The 16 x 2 LCD character display is easily programmed to display up to four model parameters per screen page.
Pushbutton 1 (up arrow): The leftmost pushbutton advances to the next LCD screen page. Holding down this button brings up the
configuration menu.
In Menu mode, this button increases the value of the parameter.
Pushbutton 2 (down arrow): This pushbutton returns to the previous LCD screen page.
In Menu mode, this button decreases the value of the parameter.
Pushbutton 3 (Disp/Reset Max): pressing this pushbutton briefly causes the Dashboard to toggle between Max and Live modes. In
Max Mode, the parameters displayed have a carat (^) next to them to indicate they are the max parameters recorded. Note that some
parameters are not captured in Max Mode – these are displayed with “***”. Figure 6 shows which parameters have the Max feature.
In Live Mode, the data displayed are the live values received from the Transmitter.
Holding down this pushbutton for approximately two seconds zeros the Max parameters.
In Menu Mode, this pushbutton takes you to the next menu item.
Pushbutton 4 (Mute/Power): When the unit is in operation, pressing this button mutes or unmutes the audio portion of the
Dashboard, as well as turning off power. What happens when the mute button is pressed briefly depends on the state of the audio
system:
•If the audio is unmuted, and no alarm beeps are in progress, pushing the button causes the Dashboard to go into “Mute All”
state. No beeps will be heard in this state.
•If the audio is in “Mute All” state, pushing the button causes the Dashboard to go into “Unmute” state. All beeps will be
heard in this state.
•If the audio is unmuted, and alarm beeps are in progress, the Dashboard will go into “Mute Current” state. This state mutes
only the currently sounding alarm to be muted. All other beeps will be heard, and the currently sounding alarm will be heard
once the alarm condition occurs again.
When the Mute/Power button is held for approximately 2 seconds, the Dashboard is powered off.
Note: Pressing any of the keys when the power is off powers up the Dashboard.
Note: The Dashboard will power off after approximately 5 minutes when no signal is being received, and no buttons are pressed.
Configuration Menu
Holding the Pushbutton 1 (up arrow) button on the SRX puts the unit in Menu mode. Holding it again takes you out of Menu mode.
In Menu mode, pressing/releasing up and down arrows varies the parameter, and pressing Pushbutton 3 (Disp/Reset Max) takes you to
the next menu item. All of these parameters can be selected and changed while your model is in the air!
Here is a description of the menus:
•“Vario Avg Secs” – This setting controls the averaging period of the variometer, in 10ths of a second units. For faster
response, lower periods are recommended, but in rougher air longer periods may be required to avoid false alarms. Pressing
up/down arrows changes the averaging period.
•“Vario Sinkrate” – this setting controls the minimum sinkrate. Normally, this would be set to the standard sinkrate of your
model, i.e., the rate at which it descends in smooth air with no thermals. When you descend at a rate greater than this
sinkrate, the variometer will start to sound, as described in the “Variometer” section above. Pressing up/down
arrows changes this parameter.
•“Vario Climbrate” – this setting controls the minimum climbrate. When you ascend at a rate greater than this climbrate, the
variometer will start to sound, as described in the “Variometer” section above. Pressing up/down arrows changes this
parameter.
•“Vario Freq Shift” – This setting changes the amount the pitch changes as the climbrate increases/decreases. If you are not
hearing enough change, increase this parameter, and vice versa for too much frequency change.
•“Total Energy %” – this adjusts the scaling of the Total Energy Compensation calculation. 100% means that Kinetic Energy
is converted into Potential Energy directly, i.e., any change in airspeed is assumed to directly negate any change in altitude.
Less than 100% reduces the degree which airspeed change affects Total Energy, and increasing it above 100% increases the
amount.
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Ready for Action!
Now that you have completed basic installation and configuration of the Seagull system, it’s time to actually use it!
Power on your model as you normally would, turning on your radio transmitter before powering up the model. The Recorder’s LED
should blink normally (one flash repeating) after powering up the model.
NOTE: Always wait 15 seconds after powering down your Recorder, before powering it back on. This will ensure that the
Recorder and transmitter start properly.
Next, power on your Dashboard. Since the Dashboard calibrates several of the parameters on powerup, always turn on your model
first, then turn on your Dashboard (or turn the Dashboard power off and on after you model is turned on).
At this point, the Dashboard should display live data. By default, page one of the data displayed contains Airspeed, Altitude,
Variometer climbrate (TE compensated), and Receiver voltage. Page two of the data displayed contains signal strength, received
packet percentage, and raw climbrate (non-TE compensated). If the Dashboard displays “No Signal”, consult the Troubleshooting
section below.
Once the Seagull system is communicating, consider how you will mount and use the Dashboard. The Dashboard can be mounted
to your radio transmitter, using the supplied plastic clip with adhesive. Just remove the adhesive backing from the clip, mount the
clip on the back of the dashboard, and clip the ring around your radio’s antenna. You can further stabilize the dashboard with a strip
of Velcro on the dashboard’s bottom. Or, just hand the dashboard your crew or buddy to monitor your run, or just place it in your
shirt pocket. It is a very bad idea to take your eyes off your model during operation!
DON’T FORGET TO “ANTENNA DOWN” RANGE CHECK YOUR MODEL AFTER INSTALLATION, AS DESCRIBED
IN YOUR RADIO MANUAL!
Adjusting the Variometer
The Averaging Period, Sinkrate, and Total Energy Compensation percentage should be adjusted depending on wind conditions, plane
geometry, etc., so that the unit is silent when you are flying in still air but descending normally at your plane’s standard sinkrate.
See the above section for instructions on how to change these parameters, even while the plane is flying.
Typically, you would start with a very small Variometer Average Seconds (perhaps 0.2), and a sinkrate of perhaps 150. If the unit
“sqawks” or “honks” a lot when flying outside of thermals, start gradually increasing the average seconds until it doesn’t sqawk.
Then, adjust the Minimum Sinkrate parameter until the unit just barely does not make a constant tone as you descend due to gravity
when flying level. We recommend that the above adjustments be made with the Total Energy percentage set to 0%.
The total energy % should be adjusted (after doing the above adjustments) so that “stick thermals” are minimized. We recommend
starting at 100%, then adjusting the value up or down, so that you can pull back on the elevator and not hear lift tones.
This section describes more advanced setup and configuration. A computer is required for
this section, and some features listed require optional accessories.
Installing Temperature Sensor(s)
If you purchased optional Temperature Sensors, you will be able to monitor up to two
temperatures with your system. Plug the Futaba style connector from the sensor into the
recorder as shown in Figure 1.
Note: the Temperature Sensor lead can be easily extended with a standard servo extension
cable.
Installing the RPM Sensor
If you purchased the optional RPM Sensor kit, you will be able to measure the RPM of your
motor. Installing the RPM sensor and magnets is the most challenging part of installation,
but is relatively easy once a good mounting location is determined. Refer to our website’s
Flight support page at http://www.eagletreesystems.com for pictures of example
installations.
First find a suitable location on your engine’s motor to attach either one or two small magnets and RPM sensor. Typically, the prop
washer or prop hub are ideal locations. This will of course vary with make and model of plane. Make sure the magnets are mounted
on some structure that doesn’t “flop around,” as the magnets could hit the sensor in this case. The RPM sensor must be mounted so
that it does not move around, and is within 1-2 mm of the two magnets as they spin. On typical plane installations, there’s usually a
place where the back of the sensor can be glued to a flat surface under or over the hub which has the magnets mounted. The
Recorder kit includes four magnets. That provides you with up to 3 spares.
Installing Magnets
Once you have determined where to install the magnets, decide whether you will drill a hole so that the magnets will mount flush with
the surface, or if you will just glue the magnets to the surface. Though somewhat more difficult and permanent, mounting the
magnet flush with the surface is the best long term approach, since the mounting will be much more rugged, and the risk of imbalance
due to not mounting the magnets exactly 180 degrees apart is reduced. In fact, if the magnet is mounted flush in another metal
material, it is quite possible that no shaft imbalance will occur if you only mount one of the magnets total.
To flush mount the magnets, drill a hole just slightly larger than the diameter of the magnet size you choose, and of the same depth as
that magnet. If you decide to surface mount the magnets, thoroughly clean this area and lightly scuff it to improve adhesion. Glue
the magnets with thesidemarked with a red line facing inward (hidden), using epoxy, or other strong, suitable glue. It’s important
that the red line on the magnets faces away from the sensor once the sensor is installed. The magnets should be glued 180 degrees
apart to keep the shaft in balance.
WARNING: make sure that the magnets are glued sufficiently so that they will not detach and create a hazard, and always
wear safety glasses when your engine is running! It is also a good idea to put a piece of heatshrink tubing or electrical tape
around the magnets, to further secure them.
Using Existing Magnets
Note: if your engine already has magnets mounted for some other purpose, there’s a good chance you can use them. Take one of the
magnets included with your recorder, and put that magnet up against the previously mounted magnet. If the red line of the Recorder
magnet faces down so that the sensor can be mounted facing the side of the magnet with no red line, mount the sensor with the printed
side toward the magnet. If the side of the magnet with the red line is visible when on top of the previous magnet, the polarity is
reversed. This should work correctly if you install our sensor backwards (printed side of sensor away from magnets), though we have
not tried it.
We are often asked whether existing magnets on spark ignition engines can be used. The answer is “yes” in most cases, if you can
install the sensor near enough to rotating magnets. We have found that these engines typically have 3 magnets, with 2 magnets
mounted with one polarity, and the other one with another polarity. The easiest way to use these magnets is to install the sensor with
the printed side facing the magnets (as described below) then run the motor and see what RPMs are recorded after setting up the gear
ratio. If the RPM looks like it is only half of the correct value, double the gear ratio value you entered, to compensate for only one