I was informed (and verified) that there is a way to easily test the
302 warning system while on the ground.

- Power down the 302
- Unlock the airbrakes with the gear unlocked/up
- Power up the 302

The alarm will then sound (euro siren) after the self test is
complete. A large upwards pointing arrow will appear in the display,
different than the small speed up/down arrows, meaning I suppose that
your gear is up. You can silence the alarm by pushing the button.

Yet another undocumented feature/sound from the Cambridge 302!

- John