diode explanation

Discussion in 'General Electronics Chat' started by Boomer999, Jul 23, 2013.

  1. Boomer999

    Thread Starter New Member

    May 2, 2013
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    I just got a bag of 1n34a germanium diodes. Of the 20 in the bag there were 10 that had no continuity one way. And was getting between 250 to 380 ohs resistance in the other direction. 3 more had no continuity one way and two to three ohms resistance the other way. 7 of them had no continuity in either direction. I am new to this and unsure of what the resistance if any should be in the direction that does have continuity. Could someone please clarify for me.
    Thank you.
     
  2. absf

    Senior Member

    Dec 29, 2010
    1,490
    371
    Are you using analog or digital meter?

    Allen
     
  3. tshuck

    Well-Known Member

    Oct 18, 2012
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  4. Boomer999

    Thread Starter New Member

    May 2, 2013
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    I am using a Fluke 87 V digital multimeter.
     
  5. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,507
    2,367
    You need to have a meter with the diode test position, the regular Ohm scale is not going to work, due to the forward bias current required to measure the diode, unless it is totally shorted.
    The diode scale actually forward biases the diode and indicates the volt drop in the forward direction, in the reverse, it should show open or infinity.
    AFAIK the 87 series has the diode check.
    Max.
     
    Last edited: Jul 24, 2013
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