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SPDT switch with phototransistors

  1. Feb 14, 2010 #1
    Hi all. I am looking on how to make a single pole-double throw (SPDT) switch using phototransistors that can be activated by IR LEDs (not from a remote, i.e. in pulses, but as a single arrangement of a switch, cell, and IR LED).

    Please keep it simple, I am only doing experiments. I don't require any complicated circuits, but just using the minimal of components.
  2. jcsd
  3. Feb 14, 2010 #2


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    Staff: Mentor

    Do you want the switch contacts to be mechanical (like with a relay), or electronic (like with analog switch ICs)? What voltages and currents will the switch contacts see? You will need two receive pickups, right? To actuate the two "positions" of the pole?
  4. Feb 16, 2010 #3
    I'm using phototransistors, so of course, an electronic one. I'd also like someone to try and make a SPDT that uses one phototransistor, if not, then two or even more. Since I find difficulty in finding phototransistors, it should be the reason why I would like to hear about a single phototransistor-operated SPDT.

    I think, could a photo-darlington type transistor with three legs be used for this purpose?

    Please don't take it as a very demanding post.
    Last edited: Feb 16, 2010
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