# XVII.	Suggestion of use

* <mark style="color:red;">**We suggest you to turn-on your instrument while preparing your flight in order to be sure you get the GPS fix before starting your flight.**</mark>
* Use the strap <mark style="color:red;">**to secure**</mark> your instrument while flying.
* Electromagnetic perturbations from VHF antennas can disturb GPS signal.
* If the SYS'NAV is very hot and you fly in very cold air, **fog** can appear on the screen. It will dissipate within minutes.
* Only use the **backlight** if required. Otherwise the autonomy will decrease significantly (30%).
* A **Factory Reset** from SYS PC Tool (Configure my instrument ![](https://4250689551-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2f7Z1a7NcpMUFsb21xMs%2Fuploads%2Fz1mC6U5eDz1qVdQagn2B%2Fimage.png?alt=media\&token=2b8793fb-8952-441b-a4bc-afda51e3597f) Repair ![](https://4250689551-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2f7Z1a7NcpMUFsb21xMs%2Fuploads%2FYpVFserhok7tJo2mCBS5%2Fimage.png?alt=media\&token=20cc3ef4-7a1f-4f79-a036-314d0cefbee4) Factory reset) ables you to get your instrument back to default state (every recorded flight will be deleted).
* When you connect your instrument to a USB charger, the battery will start charging, even if the instrument is turned-off.