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Help!!

Discussion in 'General Electronics Chat' started by N.Carsane, May 28, 2014.

  1. N.Carsane

    N.Carsane New Member

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    I have a 3-Pin Phototransistor from an old Sony TV, but i don't know the pinout and what pins to use to make it act as a photodiode...
     
  2. Inquisitive

    Inquisitive Super Moderator

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    What does the label on the part say. Can it be cross referenced to a datasheet?
     
  3. Reloadron

    Reloadron Well-Known Member Most Helpful Member

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    Unless it has some part number markings on it it will be hard to say whet it is. If you are familiar with phototransistors and their operation you can sit down with it and a ohmeter and start probing it. A Google of phototransistor will bring up literally hundreds of images and pinouts. Might be a good start. Even if you could post a few images it might help.

    Ron
     
  4. dave

    Dave New Member

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  5. N.Carsane

    N.Carsane New Member

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    I've seen too many sites with lots of phtotransistors which is why i am confused, the photos are slightly blurry but you should be able to make it out. this photo-transistor came from an old Sony TV and has a casing and it's dimensions are h: 12mm w: 10mm and d; 6mm with the casing.

    I have tries using an ohm-meter and two of the connections act as a diode, but i still can't make out Vout, Vss and ground
     

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  6. N.Carsane

    N.Carsane New Member

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    http://memakingthings.blogspot.co.uk/2012/09/leds.html if this link opens the i would've thought that my IR reciver is similar to the one one the bottom left, pin 1 is ground, pin 2 is Vcc and pin 3 is data...I tried this configuration and I can confirm that it worked perfectly, thanks guys!:cool: :woot:
     
    Last edited: May 28, 2014
  7. 4pyros

    4pyros Well-Known Member Most Helpful Member

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    I was going to say its an IR receiver.
     
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  8. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    As you've presumably now realised, it's NOT a photo-transistor, it's an IR receiver IC, and can only be used for that purpose.
     
    • Agree Agree x 1
  9. N.Carsane

    N.Carsane New Member

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    It also picks up infra red from phone signals! I just discovered it as i connected The IR reciever and the output spiked when i didn't press the remote and i realised that it does pick up a few Phone signals...
     
  10. Reloadron

    Reloadron Well-Known Member Most Helpful Member

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    Your phone uses IR? What are you looking at this output signal with? I have never seen a phone that used IR for communication. Other than basic science fair projects using line of sight IR communication.

    Most IR transmitters like the ones for TV, DVD Players and such use a modulated IR signal with a modulating frequency around 38 KHz or so. The receiver receives the modulated signal and demodulates it resulting in a pulse train. These pulse trains are easily seen on an oscilloscope. When you say the output spiked what exactly do you mean?

    Ron
     
  11. 4pyros

    4pyros Well-Known Member Most Helpful Member

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    Infra red from phone signals?
     
  12. kubeek

    kubeek Well-Known Member

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    Back in those days before bluetooth and wifi phones had IrDA for connecting to other phones ;)
     
  13. Mickster

    Mickster Well-Known Member

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    Seems IR may be making a comeback for controlling entertainment centres etc.
    http://www.theverge.com/2013/4/24/4262074/is-this-the-year-of-the-ir-blaster
    Some older phones had IrDA ports for data transfer, but this got surpassed by Bluetooth.
    Looks like some engineers added the hardware back in, to provide yet another gimmick for sales and marketing.
     
  14. Reloadron

    Reloadron Well-Known Member Most Helpful Member

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    Yes, IRDA as in Infrared Data Association who developed the standard for IR communication of data between two phones with IR data ports and the phones needed to be line of sight and in close proximity to each other. I don't know of any common house phone used for voice communication that uses or used IR communication. Beats the heck out of me. If anyone has a link to a phone like this (common voice communication IR phone) I would be interested in reading about it.

    Ron
     
  15. 4pyros

    4pyros Well-Known Member Most Helpful Member

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    Maybe but its the first I have hard of it.
    My 1st guess would be he has a vary old phone.
     
  16. Mickster

    Mickster Well-Known Member

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    HTC One and Galaxy S4 aren't relatively old phones.
     
  17. 4pyros

    4pyros Well-Known Member Most Helpful Member

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    And they have IrDA?
    I have had too many Apples to notice.
     
  18. Mickster

    Mickster Well-Known Member

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    Check the link Andy, seems that some things not-Apple are making a comeback.
     
  19. Reloadron

    Reloadron Well-Known Member Most Helpful Member

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    My cell phone is a Galaxy S4 and yes, it has an IR transmitter. I believe the Galaxy S5 also has one. Ready for this? Why does it have an IR transmitter? Why of course so I can control my TV, DVD Player, and of course my set top cable TV box. I kid you not, it can actually control those and many more IR devices. I have no clue how many, if any people use it for those functions but rest assured it will indeed do it. Yes, out of curiosity I actually did program it to do those things. I never use it for any of that stuff but it will do it.All sorts of applications out there for the IR transmitter. :)

    Keep in mind that none of this has anything to do with a phone in the sense of the word phone. The Galaxy S4 and S5 can run all sorts of amusing applications but I seriously doubt when the poster mentions:

    any of these device applications are what he had in mind.

    Ron
     
  20. 4pyros

    4pyros Well-Known Member Most Helpful Member

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    Thanks for the link, who would have thought.
     
  21. N.Carsane

    N.Carsane New Member

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    I attatched my DMM to the output of the IR receiver and when ever i pressed a button on the remote i saw aprox a 2V AC reading and my phone was near the receiver, i noticed that every time i sent a message i saw o.2V AC Pulses, my phone isn't very new (Samsung ch@t 335) but it uses some kind of wave to send data to other phones (this is in the UK) other countries have different carrier frequency and the IR reviever somehow managed to pick this signal up. I'm pretty confident that there was no intererance or static being picked up in the circuit and the general output reading when no signal was picked up was 0.01V AC. So far i have been able to predict a text message a few seconds before my phone goes off, it has work all the time! :cool: Freaky stuff!

    However the articles i read about the frequencies for the IR reciever and phones but i still can't make a valid conclusion to why this is happening.

    Does someone have an explanation? :confused:
     

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