MyFlyDream MFD AAT, Руководство пользователя

Страница: 23 / 32

Options menu:
Item Remark
VER OFFSET
Press the SET button repeatedly, and VER OFFSE value will vary
between -16 to 15, the whole OSD screen picture moves
the corresponding pixels in the vertical direction.
HOR OFFSET
Press the SET button repeatedly, and HOR OFFSE value will vary
between -16 to 15, the whole OSD screen picture moves
the corresponding pixels in the horizontal direction.
COMPACT MODE
Press the SET button to enable or disable the COMPACT MODE.
The OSD picture will occupy one less row in COMPACT mode.
Enable this option if your monitor is not able to display the
whole OSD picture.
8. FAQ
1). Q: When do I need to make the hard iron calibration?
A:
When you change the equipment used on the tracker (Rx, antenna), or feel the accuracy
of the tracker is not ideal, you may try to make a hard iron calibration. This is simple, fast,
and can be cancelled at any time by restoring the factory settings. If you know some
principles of the hard iron calibration, it will help you better use this feature.
You may already know that the tracker relies on the internal electronic compass to
determine its own direction so as to align the azimuth of the plane. The intensity of the earth
magnetic field is very weak and varies dependent on the region, which is generally about 0.6
gauss. The various electronic devices and ferromagnetic substances in the tracker may
generate magnetic fields sufficient to affect the accuracy of the tracker, e.g., the steering gear
and built-in motor using permanent magnet. Magnetic fields generated by the load users
apply on the tracker, e.g., image transmission receiver and panel antenna, may also affect the
accuracy of the tracker.
In the process of hard iron calibration, the tracker spins and analyzes the intensity of
the magnetic field around the sensor. Because the steering gear or the electronic circuit
generates different magnetic field and geomagnetic field, and they spin with the sensor, we
have ways to separate the parameters disturbing the magnetic field in the spinning process
to compensate the future sensor data and obtain better tracking accuracy. So whenever you
add a device to the tracker, it is necessary to make a hard iron calibration.
You may see from the above that some magnetic interference cannot be corrected even
by the hard iron calibration. For example, if there is a ferromagnetic substance on the tripod.
Since it does not spin with the tracker, the tracker will always regard the magnetic field it