Mystery Object - Mystery no more! - Page 1
Forum section: electronics / projects

author: Kintekobo
author_rank: Regular Contributor
timestamp: August 05, 2015, 08:42:48 pm
content: I have had this in my salvaged components box for some time now and I know I removed it from some piece of equipment that was duff but had salvageable parts. Problem is I have no idea what it could possibly be and I can't remember what it came out of. I had thought that it was a mercury type tilt switch but it doesn't change conductivity when moved.I have attached a picture and to describe it - it is a cylinder about 16mm long and 4mm in diameter with a terminal protruding from one end. The outer case is a yellow metal and looks to be brass. There is no continuity between the center electrode and the case, and the capacitance is just over 1pF.So any ideas what it is??

author: German_EE
author_rank: Super Contributor
timestamp: August 05, 2015, 09:00:53 pm
content: Do you get zero ohms with the cylinder in all positions? It looks like a mercury tilt switch to me.

author: Kintekobo
author_rank: Regular Contributor
timestamp: August 05, 2015, 09:02:55 pm
content: Not a tilt switch, which was my first thought. It reads open circuit in all positions and doesn't 'rattle' if you shake it which it would if it had mercury inside.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 05, 2015, 09:42:21 pm
content: Spark gap? Gas discharge? Something to do with vacuum or near vacuum, and the conductivity of ions therein? If there's a peculiar window on the end, maybe a Geiger-Muller tube?Tim

author: Kintekobo
author_rank: Regular Contributor
timestamp: August 05, 2015, 10:03:32 pm
content: I think the end caps would be too leaky for a gm tube. Just what looks like abs plastic. Also, it came out of a piece of consumer electronics I'm pretty sure. This thing has had me stumped!!!

author: Fraser
author_rank: Super Contributor
timestamp: August 05, 2015, 10:56:06 pm
content: Spring based vibration sensor?Connect it to a lamp circuit and see if the lamp flickers if you flick the unit. These are used as tamper or bump detectors. They are also to be found in kids toys, LED lit shoes etc.If it is such a vibration sensor you will find a long spring attached to the centre pin and it swings around under its own weight inside the tube until enough movement causes it to touch the cylinder and close the circuit to the circuit monitoring it. A multimeter continuity test may or may not be fast enough to detect the output as it is often a short duration contact time.Aurora

author: tron9000
author_rank: Frequent Contributor
timestamp: August 06, 2015, 08:00:55 am
content: Quote from: Kintekobo on August 05, 2015, 09:02:55 pmUnless the worst has happened and its all leaked out?

author: Kintekobo
author_rank: Regular Contributor
timestamp: August 06, 2015, 09:44:13 am
content: Quote from: Aurora on August 05, 2015, 10:56:06 pmAurora - Now that's a thought! I haven't tried shaking it with perhaps the scope connected to one side and +5V the other and see if it triggers. I will give that a try and report back.Chris

author: rickselectricalprojects
author_rank: Regular Contributor
timestamp: August 06, 2015, 09:50:23 am
content: That looks like a geiger muller tube

author: mikerj
author_rank: Super Contributor
timestamp: August 06, 2015, 10:54:03 am
content: Quote from: rickselectricalprojects on August 06, 2015, 09:50:23 amIt has the same silhouette, but that's about it.

author: McBryce
author_rank: Super Contributor
timestamp: August 06, 2015, 11:05:30 am
content: I'd say it's an older version of these:http://www.ecvv.com/product/3705645.htmlPossibly out of an arcade machine ?McBryce.

author: Deathwish
author_rank: Unknown
timestamp: August 06, 2015, 11:09:49 am
content: Quote from: McBryce on August 06, 2015, 11:05:30 amHmm,my nemesis as a child in Bognor arcades..

author: Kintekobo
author_rank: Regular Contributor
timestamp: August 06, 2015, 03:56:35 pm
content: Quote from: McBryce on August 06, 2015, 11:05:30 amMcBryce I think you are right in that. I can't seem to get it to do anything when I put 5V on one side and the scope on the other set to single-shot but it could be faulty. Only one way to find out I suppose..........

author: Kintekobo
author_rank: Regular Contributor
timestamp: August 06, 2015, 04:05:59 pm
content: And the prize goes to <Drum Roll> .... McBryce.See attached picture. Bit out of focus but inside the tube is a spring. I hadn't wanted to open it until I had a reasonably good idea as to what it was in case it was destroyed, but the bottom came off easily.At last I can sleep at night knowing what it is

author: Fraser
author_rank: Super Contributor
timestamp: August 06, 2015, 04:31:07 pm
content: Cough, Cough .... what about meAurora said:"you will find a long spring attached to the centre pin and it swings around under its own weight inside the tube until enough movement causes it to touch the cylinder"Was I wrong ?Only being precious, I like these "do you know what it is" challengesAurora

author: Kintekobo
author_rank: Regular Contributor
timestamp: August 06, 2015, 04:41:27 pm
content: Quote from: Aurora on August 06, 2015, 04:31:07 pmAurora - can you ever forgive me. Of course you win the prize. Sorry McBryce you were pipped at the post. Still it was fun while it lasted. Now I just need to find a use for it. Suggestions on a postcard.........Aurora

author: Fraser
author_rank: Super Contributor
timestamp: August 06, 2015, 05:28:31 pm
content: You are forgivenAurora

author: Pjotr
author_rank: Frequent Contributor
timestamp: August 06, 2015, 06:11:30 pm
content: Quote from: Kintekobo link=topic=51932.msg725365#msg725365Build a pinball machine around it..........

author: McBryce
author_rank: Super Contributor
timestamp: August 07, 2015, 10:46:12 am
content: Of course the prize should go to Aurora! What was the prize by the way?Suggestion (not on a postcard): If you have a small child, add a few LEDs to any of their rattle toys via the switch. Add cap and charge circuit so that it lights for longer as soon as enough charge has built up.McBryce.

author: Kintekobo
author_rank: Regular Contributor
timestamp: August 17, 2015, 07:48:16 pm
content: Ah the prize, worth more than mere cash or trinkets - My undying respect!Don't have any kids to give the rattle idea to, though it is a good one. I'm afraid my ideas run on more 'disturbed' lines. The current plan is a rather childish prank on an good, though currently annoying, friend with a rather swish new car. An Arduino ATTiny, a small piezo speaker, a battery and the sensor in a small package hidden under the passenger seat. When the car goes over a bump it will make a squeak. A squeak in his new car!!!! Should drive him crackers trying to find it.

author: Falcon69
author_rank: Super Contributor
timestamp: August 18, 2015, 05:25:11 am
content: You could move to California and carry it in your pocket hooked up to a buzzer. When the buzzer goes off, you know there's an earthquake happening.I've never seen one, pretty simple device to sense vibration. I like it.