There are a lot of possibilities to mount a carriage warning in the plane. The most of people use mechanical switch, the weak spot is the actuating lever.

Magnet switches offer for this an ingenious alternative. It is closed system and so fail-safe!

Following set though with more expensive, but high-quality relays:

• 1 pc. piezo-buzzer
• 2 pc. magnet relays with soldered cable
• 2 pc. bar magnets
• 3 m cable

Just minimal solder work necessary!
 

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