IMMERSIONRC EZANTENNA - AN IDIOTS GUIDE V0.03 LAST UPDATED 12TH NOVEMBER 2013. (WORK IN PROGRESS)

INTRODUCTION

This guide will help you get your head around the mystical antenna tracker system from ImmersionRC. Its name suggests it

should be easy to configure and use but in-fact many people have found it to be a bit of a head-ache, thankfully though once

you do get it setup it is actually pretty simple to use

Please Note: At the end of this document there is an appendix: it includes an over-view of the telemetry & status screens, a

break-down of the menu options and a recommended upgrade to protect your EzAntenna from potentially failing.

HOW DOES IT WORK?

Understanding how the tracker works will help you grasp how to set it up and use it successfully: The tracker its self has no

internal GPS or compass so it relies on firstly being told where it is (this is done by placing the craft next to the tracker as a

reference) and which way it is pointing. Secondly it relies on the craft relaying its current position so it can use simple maths to

triangulate where the craft is (relative to its own position) and then point the antenna in the correct direction.

For the tracker to work you will need to have a compatible telemetry device which is either an EzOSD or a TinyTelemetry which

should be connected to an audio channel on your video transmitter (this is how the data is sent to your tracker). Once your

tracker is connected to the audio output of your video receiver it will decode the telemetry data from your EzOSD or Tiny

Telemetry.

WHERE TO START

Before we configure the tracker and talk about using it in the field there are a few things you need to do first.

Note: To save destroying your servos please do not connect them until this guide prompts to you do so.

INSTALL THE LATEST FIRMWARE

First of all you need to make sure you’re running the latest firmware (at the point of writing that was v1.14).

Head over to http://www.immersionrc.com/

Select products.

Find the EzAntenna section.

Select Firmware/Downloads.

Download ImmersionRC tools & the latest firmware.

Unzip the firmware.

Install ImmersionRC tools.

Once you have installed the ImmersionRC tools follow the following instructions to upgrade your firmware.

Load ImmersionRC tools.

Select EzAntenna.

While pressing the middle button on your EzAntenna connect the USB lead to the PC (this will put the device into

programming mode).

You will now be able to click the ‘Upload Firmware’ button in the ImmersionRC Tools application.

Browse to the firmware file you have un-zipped and select it.

Your EzAntenna will now be upgraded.

If the upgrade was successful when you power up the EzAntenna it should now report the latest version number.

STARTING FROM A CLEAN SHEET

Now your tracker is installed with the latest version of the firmware lets tidy things up a bit before we begin with the

configuration steps.

BEARING CALIBRATE

In the menu system find your way to ‘Bearing Cal.’ and set the value to zero degrees. This is one of the main things that catches

people out; if you can’t point your tracker due north this bearing value is there to offset the pan position, so if your bearing is set

to 90 degrees; when you set the tracker manually to zero degrees it will actually be at 90 degrees which means if you’ve set your

antenna to point dead straight forward at zero degrees pan you’ve not actually got it facing the right way at-all.

SERVO SET

This option is used to manually adjust and test the tracker however if this option is set while you’re in the field your tracker is

rendered useless because its expecting a manual input only.

Before we setup the tracker we need to make sure we do the following:

Change the Servo Set option to Yes.

Set the Pan degrees to zero.

Set the Tilt degrees to zero.

Change the Servo Set option to No.

US/360

http://www.immersionrc.com/

This option (microseconds per 360 degrees) is used to define what sort of signal the tracker is going to give to your servos to

make them carry-out a full turn, this settings is very important and it also varies from servo to servo depending on the make and

model.

The purpose of this option is to translate the servo language (PWM: pulse width modulation) to degrees, so when you select say

90 degrees your servo will actually turn the tracker to 90 degrees instead of some random angle.

To start with I’d advise setting both of these values to 1000 until everything is connected up, this will save your servos from

destroying them-selves or the tracker if they try and turn too far to start with.

PAN & TILT OFFSET

These will help you tweak the position of your tracker so zero degrees is facing perfectly forwards.

Please set both the Pan & tilt offset to zero at this stage.

GETTING THE TRACKER WORKING

Here starts the fun bit! At all times be vigilant and if you hear your servos binding make sure you turn off the tracker straight

away or you risk burning out your servos and/or the tracker itself.

CONNECTING UP THE SERVOS

To find the neutral point for your tracker I suggest you do the following:

Assemble your tacker.

Connect both the Pan and Tilt servos.

Power up the tracker.

Observe the position of the antenna.

Adjust the servo horns/drive cogs on both the Pan and Tilt servos until the antenna is facing as close to forward as

possible.

ADJUSTING THE PWM SIGNAL

Now we need to get the tracker talking to the servos in the correct manner, there is quite a simple method to getting this right:

Enable Servo Set (From the menu system set Servo Set to Yes).

Change the Pan angle to 90 degrees.

Observe the actual angle of the tracker (The tracker should rotate clock-wise, if it does not: find the PAN reverse option

and enable it).

Go to the Pan us/360 option.

Adjust the us/360 value until your tracker is pointing 90 degrees (clock-wise) from dead forward.

Repeat the same process on the Tilt channel (Note: A positive tilt angle should cause the tracker to lean backwards so the

antenna is pointing towards the sky).

TRIMMING THE TRACKER

If your antenna does not point perfectly forwards when everything is set to zero go to the Pan & Tilt offset options and adjust

accordingly.

Note: You may need to tweak the us/360 values after doing this.

SETTING THE ROTATION LIMITS

Now you’ve got a tracker that knows where its front is and knows how to understand angles you will now need to set the limits:

A good starting point is to set the following:

Pan Max: 180 degrees.

Pan Min: -180 degrees.

Tilt Max: 90 degrees.

Tilt Min: 0 degrees.

Using the servo set option pan and tilt the antenna fully until you observe any binding or unusual behaviour. Also check that the

tracker can reach the full extents of travel, if there are problems set the maximum pan & tilt values accordingly to prevent any

damage to your servos or tracker.

AUDIO / TELEMETRY FEED

The EzAntenna works by receiving the telemetry data from your EzOSD or TinyTelemetry over an audio channel.

You will need to connect your receiver to your tiny telemetry using the 4pole 3.5mm connection.

From the home screen on your EzAntenna you will be able to scroll down to the Audio Levels view, when your plane is powered

up and the EzAntenna is connected to the receiver you should see the audio-level bar moving.

In addition to the audio levels you can also check the quality of the packets (data) being sent to your tracker from your craft, if

they are communicating properly you should see good packets being reported, some bad packets are ok but ideally you should

be getting a good packet rate of at least 90%.

If you are not getting good packets or your audio levels are too low or too high there are a few things you can try:

Check that your video receiver’s audio channel is connected to the 3.5mm jack on the EzAntenna and that you are using

the correct cable (see appendix for cable details).

Make sure you are using the correct audio channel (left or right) on your receiver.

Check that the audio output of your EzOSD/TinyTelemetry is connected to your video transmitter.

Check that the telemetry speed (slow, normal or fast) matches on both the tracker and the EzOSD/TinyTelemetry (see

the menu options in the appendix for further details).

Try changing the telemetry audio level on your EzOSD/TinyTelemetry using the ImmersionRC tools.

TESTING THE TRACKER

Once you are happy with your settings you are now ready to test your tracker.

Note: Be ready to power off the tracker should you observe any binding or if anything should jam up.

Make sure ‘Servo Set’ is off (set to No).

Scroll down through the menu and find ‘Servo Tst’ (Servo Test).

Set ‘Servo Tst’ to Yes.

Your tracker should now pan & tilt through its full range, it’s worth noting when the tracker hits 180 degrees (or its maximum

pan angle) it will rotate fully the opposite way and then continue along with its rotation.

If the tracker appears to be behaving you’re ready to take it out to the field!

IN THE FIELD

This section will help you get your tracker setup at your flying field and successfully tracking your craft!

PREPERATION

Once you get to the field there are five things you need to achieve before flying:

Setup your tracker and make sure its powered-up and working

First of all make sure you have disabled both Servo Test and Servo Set.

Power up your transmitter and craft; and allow it to get a GPS fix.

Set the home position of the tracker (We’ll go into more detail in the next two sections).

Set the bearing (degrees from north) of the tracker (again we’ll go into more detail).

SETTING HOME

As mentioned at the beginning of this guide the tracker does not have an internal GPS module so it is completely un-aware of its

location. To get around this we need to place the craft (once it has got a GPS fix) next to the tracker and use the crafts GPS fix as

‘home’.

Confirm that your crafts EzOSD or TinyTelemetry system has got good GPS lock and that it is communicating with the

tracker (See the details of the Telemetry screen in the appendix to see your current GPS fix stats).

Place the craft as close to the tracker as possible.

Access the menu system (by clicking the middle button) and select ‘Set Home’.

The position of your tracker should now be recorded, proceed to calibrate the heading bearing.

BEARING CALIBRATION

The tracker now needs to know which direction it is facing (the front should be where your antenna points when the Pan, Tilt

and Bearing Cal. angles are all set to zero degrees).

This bearing value can be entered manually by taking a reading using a compass, then selecting the “Bearing Cal.” Option in the

menu system and entering the value.

Or by using the trackers auto calibration feature: To use this feature you need to follow these basic instructions:

Enter the menu system and select ‘Calibrate’, you will then be presented with this screen:

Once you see the screen above: pickup your craft and walk it approximately 30 paces perfectly in-front of your tracker

and place it down on the ground.

Leave the craft where it is, walk back to your tracker and press the middle button (your trackers bearing is now

calibrated).

Recover your craft, you’re now ready to fly!

It’s always good practice to perform some line-of-sight test flights first and get someone to keep an eye on the tracker to be sure

its pointing in the right direction and following the craft.

If you have any problems check that Servo Set is disabled, confirm you have a GPS fix and repeat the calibration steps.

Enjoy!

APPENDIX

STATUS SCREENS

To browse through the status screens use the top and bottom buttons (up & down) to switch between screens.

Screen Details

Telemetry

Corrent position (latitude), altitude (meters) and number of satelites locked (bottom right).

8 or more satelites represents a GOOD GPS Fix.

EzUHF link quality

This is only available when using the EzOSD & EzUHF with the RSSI expansion cable.

Power status

Voltage, current draw (amps) and current usage(miliamps per hours).

This is only available when using the current sensor.

Tracking

The plane’s current altitude (above launch point), distance from the launch point, the bearing (pan angle) and inclination (tilt angle) of the antenna required to point to the plane.

Packet Status

Overview of good and bad packet data from the EzOSD/TinyTelemetry. This shows you how good your audio link is.

Audio Levels

The EzAntenna requires a clean and well modulated audio link to the EzOSD/TinyTelemetry on your craft.

CONNECTIONS

MENU OPTIONS

To access the configuration menu press the middle button on your tracker.

Menu Option Description

Set Home Records the current position as Home

Calibrate Begins the bearing calibration process.

Bear. Cal Current calibrated bearing (or input your own manually).

Servo Set Manual servo set mode.

Pan Deg Pan degrees (when in manual servo set mode).

Tilt Deg Tilt degrees (when in manual servo set mode).

Pan us/360 Pan servo micro-seconds per 360 degree rotation.

Til us/360 Tilt servo micro-seconds per 360 degree rotation.

Tilt max Maximum degrees of tilt (backward/up movement).

Tilt min Minimum degrees of tilt (forward/down movement).

Pan min Minimum degrees of pan (clockwise rotation).

Pan max Maximum degrees of pan (anti-clockwise rotation).

Pan offset Degrees of pan offset or ‘trim’.

Til offset Degrees of tilt offset or ‘trim’.

Pan Rev. Enable pan servo reverse.

Tilt Rev. Enable tilt servo reverse.

Servo Tst Enter servo test mode.

AutoHome Enable auto home position setting (when a GPS lock is made).

Servo Spd Servo speed (the lower the value the faster the speed).

Telemetry Telemetry speed, this must be the same as your EzOSD/TT.

LCDContrass LCD Contrast, the higher the value the darker the text.

Exit Return to the status/telemetry screens.

RECOMMENDED UPGRADE

There is a major weak point on the EzAntenna board, it’s a multi-layer PCB, the power +5v track from the BEC connection is

tucked away in the middle of the board and it’s almost as thin as a human hair which means its prone to burning out which will

render your EzAntenna useless.

The reason behind this track burning out is the simple fact the servos draw far too much current especially if they bind or are

turning a big load.

To prevent your EzAntenna failing there is a very simple upgrade: you need to join the middle pins of one (or both) of the (pan /

tilt) servo ports to the middle pin of the BEC port with a short length of wire, this bypasses the weak track and prevents it from

being destroyed by current spikes when the tracker is working hard.

(The image above shows a tracker that has been modified in this way).

AUDIO TELEMETRY DATA INPUT CABLE

This is a standard 3.5mm 4-pole jack. The telemetry data audio-stream must be presented on the RIGHT audio channel.

(Therefore Only pins 1 and 3 need to be populated, video and audio left are optional).

(This is the standard ImmersionRC / FatShark AV cable configuration)

Pole Function

1 Ground

2 Video

3 Right (Telemetry Audio)

4 Left