Microphone for watch movement

thingiverse

This is a microphone to used for listening to the movement of a mechanical watch. It plugges into your PC or laptop, just like a normal microphone. Use timegrapher software (many can be found online) in order to get a diagnose about the performance of the watch. The microphone will hold many sizes, without the need to remove the strap. Two pegs holding the watch onto the microphone can be repositioned if needed for getting the best fit. The (gentle) pushing force of the pegs comes from a rubber band, which is crossing the open space. This makes for a nice 'safety net' incase the watch should slip. Rotate the microphone to test the movement in 4 positions. Clamp teh movement upside-down to test the remaining 2 positions. The microphone is made out of non-magnetic materials, important for mechanical watch movements. The main part is the 27mm piezo element. This can be bought online and is fairly cheap. It is soldered to a headphone wire. The rods are made from a 3mm carbon (or glass) fiber kite stick. Instructions: Printing: No support needed, orentation is all upright, print the peg twice. Clear out the holes with a 3mm twist drill bit, making sure the high block slides nicely over the guides. 3mm kite stick: Cut 2 lengths of 70mm for the sliding guides, 2 lengths of 18mm for the pegs and 2 lengths of 12mm for the rubber band fixation. Press fit the rod into the holes. Piezo element: Guide the headphone wires though the hole on the back of the high block. Remove the existing wires of the piezo element en solder the headphone wires to these connection points. Use double sided foam tape to stick the piezo element into the block. Make sure the element is not touching the block. Use a small zip tie as a strain relief like shown in the pictures. Rubber band: The diameter is about 50mm, route the band like shown in the pictures and secure it with the 12mm pins. Usage: Clamp a watch or a watch movement into the microphone. Best results come from the crown being in the middle of the piezo element. Increase the microphone volume and boost levels to maximum and switch off any enhancements. I tried using a battery powered guitar amplifier; the microphone in the input where the guitar normally goes and the headphone output of the amplifier connected to the microphone input of the PC. This gave a nice clean signal, but make sure you first bring down the volume and boost levels of the PC.