Dumb diode question

Discussion in 'General Electronics Chat' started by rockboy, Dec 30, 2008.

  1. rockboy

    Thread Starter New Member

    Dec 7, 2008
    Sorry but i have what is probably a really dumb questions. I am wanting to use a whole bunch of diode in a project i'm working on, the problem is the the only diode i have on hand are the 1n4004. When testing the diode hte resistance one way is O/L on the multimeter which make sense. But when i switch it arround the resistance is 1.5M ohms, which is way to high for the application. I don't get it, i'm using these in kits else where and they seem to be fine.

    Why would the resistance be so high? Does it need to be above a certain voltage before it lets anything pass?

    Many Thanks
  2. flat5

    Active Member

    Nov 13, 2008
  3. mik3

    Senior Member

    Feb 4, 2008
    Test it with the diode test function of the multimeter. In the reverse direction you will read OL and in forward direction you will read about 600 (this is the voltage drop across the diode).