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Few questions about homemade IrDA module

  1. Feb 17, 2010 #1
    First of all, I'm not an electrician, I'm a medical student who occasionally grab a soldering iron for some fun. So if I'm asking something really stupid, I'm sorry.
    I found scheme forIR transciever on http://www.hardwaresecrets.com/article/86/2 [Broken] and I'm plannig to build it. I was wondering is it ok to rearrange circuit (attached picture, left side) in order to bring photodiode and LED physically close and to reduce wiring, and is there a "wrong and right" way to connect photodiode and LED (I mean does polarity matters and how can I distiguish anode from cathode)
    Thanks everyone

    Attached Files:

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    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Feb 17, 2010 #2


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    Welcome to PF Gorstak.

    Electronic schematics show the electrical connections between components in a easy to read format, not the physical locations of the components relative to each other on the board.

    Yes, there is a polarity for semiconductor devices such a LEDs and photo diodes. See the flat area next to the cathode terminal of this LED.
  4. Feb 17, 2010 #3


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    LEDs are also supplied with the anode (+) lead longer than the cathode (-) lead.
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