Mistake in IR tranceiver circuit

Discussion in 'General Electronics Chat' started by MPYC, Apr 17, 2015.

  1. MPYC

    Thread Starter New Member

    Apr 17, 2015
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    0
    Hi dears.
    I designed a circuit for sending and receiving infrared signal. its range is about 1 meter but it have to pass 2 7 millimeter wholes. I used common 5mm IR emitter and receiver diodes. VCC2 and VCC1 are 12V for ground1.
    may you please check my my circuit and see if I have weakness in circuit?
    thanks all.
    [​IMG]
     
  2. MikeML

    AAC Fanatic!

    Oct 2, 2009
    5,450
    1,066
    I see no way of sending data? Key the 555 on/off?
    To check the biasing of the IR photo-diode, I would need to know the partnumber?
    What demodulates the received wave?

    Why not just use the IR modules designed for TV remote control (TSOPxxxx)?
     
  3. upand_at_them

    Active Member

    May 15, 2010
    246
    29
    How much current can your 555 source? If it's not much then you would need to have the 555 drive a transistor to switch current to the LED. And 12V/100=120mA. Is that what you want for your LED? Is it high enough? Is it too high for continuous operation?
     
  4. MPYC

    Thread Starter New Member

    Apr 17, 2015
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    IC's part number is NE555 and its frequency set on 7kHz. 555 just produce a simple continuous pulse. pick voltage on LED is about 1.35V and the voltage that drop out over R18 is about 9.75V. LED is 5mm IR once.
    if other parameter is necessary please tell me.
     
  5. MPYC

    Thread Starter New Member

    Apr 17, 2015
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    guys, have you checked my circuit?
     
  6. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Connect pin 4 of the 555 timer to Vcc1.
     
  7. MPYC

    Thread Starter New Member

    Apr 17, 2015
    8
    0
    distance of sensors(emitter and receiver) and boards are about 2 meters. I attached image of sensors.
    I don't have any problem with 555 and emitter diode because when I check it with phone`s camera I see that it work.. but in emitter part after some days or months system can not sense any signal.at this time, I touch terminals(I attached its image too) or I open wires and close them again, problem solved.
    or coupler capacitor C16 brake and pass DC signal.
    any idea?
    [​IMG] [​IMG]
     
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