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A simple non latching,I.R.switch to supply 90 ma .

  1. Mar 18, 2010 #1
    I have made an onboard uncoupling device for my model railway,It works perfectly using the circuit from a toy helicopter.Can anyone suggest a suitable circuit to make myself?
    I wish to use a 3.7v battery and the device uses a coil drawing 90 mA for 3 seconds from 1-2 metres range.
  2. jcsd
  3. Mar 18, 2010 #2


    User Avatar

    Staff: Mentor

    Can you use a laser pointer as the remote control? If so, then just a photodiode sensor, a comparator, and the relay should be able to do it.
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