Raymarine A Series A50 User's Reference Manual page 18

Simulator
Your A-Series display includes a simulator mode that enables you to
practice operating the unit without data from a GPS antenna or
transducer unit.
Note: The simulator will NOT display any real-data, including any
safety messages (e.g. those received from AIS).
To turn the simulator ON or OFF:
1. Press and hold the PAGE/MENU button to display the setup
menu.
2. Use the trackpad up / down keys to select System Setup.
3. Press trackpad right to select the System Setup options.
4. Select the Simulator option
5. Select ON or OFF as required.
6. Press the OK key to return back through the menus.
18 A-Series display - User reference manual