On 1 February 2011 05:33, Mark Rages wrote: > On Mon, Jan 31, 2011 at 11:21 PM, Dr Skip wrote: >> >> >> I need some help identifying a component in the attached pic (size and >> quality reduced to list-acceptable numbers, so hopefully still clear >> enough). I don't usually use components this small, and we won't even >> go into my eyesight... ;) >> >> This is a key fob camera/recorder. It's been flaky since purchase and >> while it had random 'bad' periods, it's unresponsive now, so I opened it >> up. Under the battery is a large smd microcontroller. Upper left is a >> mini usb and upper right is an micro SD card slot. >> >> Funny thing is, there is an unattached component lying on top >> of the SD card holder (see pic). It's a long thin 'can' with 2 leads. >> Pulling the battery back, I see an outline of the same shape screened >> onto the pcb, with 2 pads that match this escapee component perfectly. >> [see the area between usb and SD card] >> However, there are only smudged minimal markings on the component (and >> very, very tiny at that), and none other on the pcb. >> >> I can probably solder it in place, maybe, with some luck that my hand >> holds steady enough. Big solder-glob potential I think... My guess is >> it's a crystal or a cap. Can anyone confirm by sight and also let me >> know if there might be a polarization issue, or can I put it in either >> way? IIRC, a crystal won't care, but are there polarized caps this small >> these days? >> >> The leads bend toward one direction, but I'm not sure if that's because >> they were pre-formed and it never got soldered, or it bent backward >> after soldering and broke loose and flipped over prior to case closure, >> bending the leads the other way. Each way would cause the leads to bend >> opposite from the other, so if it was a polarized component, I stand a >> chance of flipping it wrongly. >> >> Thanks in advance. >> >> -Skip > > That's a 32.768 kHz watch crystal. =A0No polarity, but somewhat > vibration sensitive. =A0Still, it will probably work when you solder it > back. > > Put a big glob of glue on it. =A0It's a bad design to have a part that > big mounted without mechanical support. > > Regards, > Mark > markrages@gmail > -- > Mark Rages, Engineer > Midwest Telecine LLC > markrages@midwesttelecine.com > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > It's almost certainly a crystal. The frequency could be almost anything up to 24MHz or so. I have a flash drive with a 12MHz crystal that's almost identical. In your case if you can't read the markings, you may be able to measure the frequency using a simple oscillator circuit and scope etc. Or you could just solder it back in place and scope that or see if it works. A dab of glue should stop it getting loose again. RP --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .