I love tin cans and electromechanic telegraph, so why not made a "microsounder" telegraph in a Altoids tin can?.
For this i use a 5 volts relay, cut off the plastic orange box and add a pcb:
I cut off part of the orange relay body.
Cut a little piece of pcb (arm) for solder over the relay contact for increse the sound.
Micro sounder solded.
Add another pcb for solder wire for distance control for the arm, and solder pins for connect line and vibroplex key.
Telegraph micro sounder finished.
Telegraph micro sounder closed. Ready to go :D
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