Can you ID this orange component?

Discussion in 'General Electronics Chat' started by daviswe, Jun 17, 2009.

  1. daviswe

    Thread Starter Member

    May 14, 2009
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    This one has me stumped. The orange component at the bottom with the dark band on left, marked 105C, N08 (or is it N08?), 1C is baffling. Looks like a 3-terminal device, but so does one of the resistors, so I think that's only a trace, and it's probably a zener or other kind of diode, perhaps, maybe even a polarized capacitor, but I can't find it in the SMD tables online...

    This is a line powered mic preamp, there's a BJT (2X) on there and two resistors and two caps and the mystery block...

    thx to anyone that recognizes this stranger...
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    Electrolytic capacitor, 1.0µF. 10X10E5 pF.
     
  3. SgtWookie

    Expert

    Jul 17, 2007
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    It's a tantalum capacitor, Bill. Correct on the 1uF.

    Note that the + side has the stripe. Electrolytics have the stripe on the negative side.
     
  4. Wendy

    Moderator

    Mar 24, 2008
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    I stand corrected.
     
  5. steveb

    Senior Member

    Jul 3, 2008
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    Actually, I believe you were correct. Tantalum capacitors are still electrolytic capacitors.
     
  6. Wendy

    Moderator

    Mar 24, 2008
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    Yes, but the polarity marking is kind of critical, and I missed it.
     
  7. steveb

    Senior Member

    Jul 3, 2008
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    I thought all electrolytic capacitors (aluminum, tantalum etc) have polarity markings. Are there some that do not? Or, perhaps you mean because the mark means plus on one type and minus on the other type.

    Still, your statement was not wrong, SgtWookie just further specified the component.
     
    Last edited: Jun 18, 2009
  8. eblc1388

    Senior Member

    Nov 28, 2008
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    Yes. Some non-polar electrolytic capacitors in my parts drawer do not have polarity indicating markings.

    However, they still have long+short legs.
     
  9. daviswe

    Thread Starter Member

    May 14, 2009
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    Would it be imposing to ask now what the lilac and brown caps are? Prefaced with..."You guys are awesome. I am the kind of person that will wear myself out finding an answer before I ask others for help, and I want you to know I appreciate it."

    I have a bunch of tants and electrolytics and they are all marked with polarity, stripes, etc. I have been tinkering in SMD for only a month and wow, what a vast landscape it is! I've found several books and online pages but none have shown colored caps, at least I assume they are caps, or this one device you have identified. I did find the resistor markings and the transistor, however.

    I'm trying to reverse engineer the ckt in the image there because I want to improve on it with an adjustable gain to make it more universal in application.

    Ed
     
  10. SgtWookie

    Expert

    Jul 17, 2007
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    They're multilayer ceramic capacitors. Either they are unmarked (most likely), or the markings are face down (unlikely). It costs extra to have capacitors marked, so most cost-concious production houses don't mark them - besides, that would make it easier to reverse-engineer their product, which they certainly don't want.

    Multilayer ceramic caps are available in a wide range of values, but most common are 0.1pF to 1,000pF. To determine actual value, you would need an accurate capacitance tester. A decent one would run you around $120 or so. Most cheap cap meters won't be capable of giving accurate readings on small pF values.
     
  11. daviswe

    Thread Starter Member

    May 14, 2009
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    I am prototyping with 1uF and will tweak them once I get the rest of the traces figured out so the schematic makes sense, then I can sim it and work out sweeps to get it down to the approximate values. I don't even have the circuit any more, I sold the headset it was in to help pay for a signal gen!
     
  12. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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    Would we be correct in assessing that this circuit board has "seen better days"? :D
     
  13. BillB3857

    Senior Member

    Feb 28, 2009
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    It looks like the board had been potted in an enclosure of some kind that has been forcibly removed.
     
  14. SgtWookie

    Expert

    Jul 17, 2007
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    ...using an icepick! :eek: ;)

    The device marked 2Xp is a 2N4401 NPN transistor, like an SO4401, MMBT4401, PMBT4401, etc.
     
  15. daviswe

    Thread Starter Member

    May 14, 2009
    13
    0
    Actually, that board has been 'examined by force' and placed back in service. It was potted, and is now again potted, and yes, it took a lot of tweezer time to expose it!
     
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