Components

Discussion in 'General Electronics Chat' started by Sam., Aug 12, 2010.

  1. Sam.

    Thread Starter New Member

    Sep 17, 2009
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  2. beenthere

    Retired Moderator

    Apr 20, 2004
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    As to the resistor, the meter reading will only be accurate with the resistor out of circuit. Otherwise, you have no idea of possible parallel paths that exist. The resistor in question is accurately described as a crispy critter. The reading may be considerably different from what the original value was, but the meter reading will be accurate as to the current value.

    As a guess, it was probably the same as the two on the left side. Check against one of them.

    The other component is a tantalum capacitor - probably 1.5 uF @ 35 volts. If it's in one piece, it's probably good.
     
  3. timrobbins

    Active Member

    Aug 29, 2009
    318
    16
    You may be lucky with the resistor - some confidence may come your way if the measured value is 2xxx. The cap would be 1.5uF 35V tantalum - the + symbol indicates the polarity of the leg.
     
  4. Sam.

    Thread Starter New Member

    Sep 17, 2009
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    Thanks. I've scraped the yellow off the cap and pcb, the cap looks fine now. Does it need replacement (If I do replace it, does it have to be tantalum?)?
    I'll try desoldering the resistor to see if it has burnt off the colour bands on the bottom.
    It measured 26 in the "200k" scale on my multimeter.
    Sorry for all the questions :p
     
  5. beenthere

    Retired Moderator

    Apr 20, 2004
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    That does not seem right, but the pic is too dark to make out color bands (I see black - black - black - gold). The reason for the resistor becoming burned might be interesting to find out.
     
  6. Sam.

    Thread Starter New Member

    Sep 17, 2009
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    Looking at the resistor, the first band is red and the last is gold. On the PCB it connects to a leg of a cap. I was thinking on trying a 2000 ohm resistor, would this sound correct?
     
  7. beenthere

    Retired Moderator

    Apr 20, 2004
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    If I were trying a replacement, I would choose a resistor that matched the two on the left. Any idea what caused the resistor to burn?
     
  8. Sam.

    Thread Starter New Member

    Sep 17, 2009
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    Nope! I've put in a 2k resistor but it didn't seem to fix the problem. Think its maybe one of the obsolete chips now.
     
  9. beenthere

    Retired Moderator

    Apr 20, 2004
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    Try to follow the foil from both ends of the resistor and see is there is some active device like a transistor involved. A transistor going short or a capacitor going bad might explain the failure. It's always fun to troubleshoot without a schematic.
     
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