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Could someone help me out, I have no idea what this tube-like thing is.

This is from a Madcatz Xbox360 drum kit pedal. The pedal stopped working and I opened the it up and found just this tube thing connected to a wire going into a controller via a 2.5mm headphone jack, that plugs into a PC or Xbox360 with a USB cable. I'm guessing it's a vibration sensor or something (for when the pedal hit's the plastic on the opposite side of this tube), and this is the only electrical component in the pedal. My best guess is that it failed and that's why the pedal isn't working, and I hope it can be replaced. The cord seems fine to me.

photo 1

photo 2

Photos: http://imgur.com/a/ab4DP

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I think this is a component identification question moreso than a repair question, as such there's no reason to close it. – JYelton Feb 27 '14 at 21:21
Before replacing it, try checking if it really has failed, because other issues can affect it. The pedal function has nothing to do with vibration or hitting the pedal, it's based on measuring if the pedal is pressed down sufficiently close to it's base, i.e. if a magnet embedded in pedal is close to this component (reed switch). Turn on the device, and try moving a strong magnet to/from the switch and see if it gives the expected signal. If yes, then the problem is with magnet positioning in that pedal; if not then replacing it might help. – Peteris Feb 28 '14 at 8:04
up vote 10 down vote accepted

That is a reed switch.

It's basically a switch that is closed by a magnet.

In your case, it looks like it has a bit of sleeving over one end, possibly to protect it from vibration, but there is nothing else unusual about it.

enter image description here

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It is a reed switch, but it's more likely your magnet has fell off your pedal than this has broken, They used to make whole keyboards with these! Test it by holding a magnet to it on one side and see if it operates.

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It looks like a magnetic reed switch. It closes when a magnet is near. Is there a moving magnet nearby to make the switch open and close? It's also possible that they could have a switch optimized to open under shock (all reeds will do so, but it's not usually desirable).

Looks like a ~2mm diameter glass type. Magnetic sensitivity varies between models (over about a 10:1 range). If it really isn't working (they rarely fail) you might be better off getting it from the manufacturer.

Here are a few Digikey options for you: http://tinyurl.com/l7sw4zu

enter image description here

Based on scaling the printed dimensions for the board, the tube diameter appears to be 2.1mm, give or take a bit.

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I would say 1.6mm based on the PCB. – Ignacio Vazquez-Abrams Feb 27 '14 at 17:08
I would say ~2mm based on the printed horizontal dimensions of 41 x 7mm and scaling! I think my method is more accurate. I get 2.1mm, so it may be a standard 2.2mm tube. – Spehro Pefhany Feb 27 '14 at 17:11
Glass reed switches are somewhat fragile. If the glass seal at the lead cracks, the switch will soon fail. The encapsulated ones are a little more durable than the bare ones. The switch is easily tested with an ohmmeter and magnet. – markrages Feb 27 '14 at 18:28

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