ImmersionRC EzAntennaTracker, Руководство по эксплуатации

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Explanation: Why ‘the further the better’?.
When a GPS is powered up, especially in the presence of a high-power video transmitter, the positional
errors can be significant until a large number of satellites have been acquired.
For long distance flight, the antenna positioning accuracy is fairly critical, so the calibration of the
antenna tracker is also just as critical. If the home location of the antenna tracker is stored when the
GPS error is large, and then if the bearing (pan) calibration is performed with the plane close to the
antenna tracker, also with its own GPS error, the bearing calibration error can be quite large.
The further the plane is positioned from the antenna tracker when the bearing calibration is performed,
the less significant this error will be.
3.3.
Tip: If flying often at the same location, mark the position of the antenna mount legs on the ground. The
position of the antenna, and the heading calibration, are stored in non-volatile memory, and will be
restored when power is next applied. This will avoid the need for any ‘home position’, or heading
calibrations each time you fly.
4. Replaying recorded telemetry data
Once a flight has been recorded, it may be replayed in order to test the antenna mount (or just to
impress your friends with your NASA-class technology).
When choosing the recording/playback device, and its settings, it is important to remember that the
audio channel which contains the telemetry stream must be recorded at a fairly high bitrate, and sample
rate, in order for reliable decoding to take place.
Audio compression techniques, such as MP3, distort the audio waveform in ways that the human ear
does not detect, but the antenna tracker will be adversely affected.
Some examples of recording/playback devices, and ‘decodability’ are shown below:
Recorder Playback Success
DV Camcorder,
25mbps bitrate, for
audio + video Apple iPhone video, Audio encoded
to 128kbps, 48kHz sample rate Approx. 50% lost packets, quite
usable none the less.
DV Camcorder,
25mbps bitrate, for
audio + video Audio: 256 Kbps, 44,100 Hz, 16 Bit,
Stereo. Very good, > 95% good packet rate.
5. Frequently Asked Questions
TBD