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pls help- mosquito racket repair

Discussion in 'Repairing Electronics' started by takne007, Apr 9, 2009.

  1. takne007

    takne007 New Member

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    hello

    i joined this forum today. i purchased a mosquito racket. now its not working. please tell me ,how can i trouble shoot this.
     
  2. forumlicker007

    forumlicker007 New Member

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    What exactly happened takne? Is it oscillating or dead?
     
  3. takne007

    takne007 New Member

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    it's not oscillating. so,how do i troubleshoot? transistor is the oscillator,right? there is a transistor.looks like a FET, actually. i don't know how to check a FET. the number is "H SD 965". the transistor is not available.please help.
     
  4. dave

    Dave New Member

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  5. blueroomelectronics

    blueroomelectronics Well-Known Member

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    Is it under warranty?
     
  6. forumlicker007

    forumlicker007 New Member

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    FET only. Might be a faulty one I guess. Replace it, before that check 1.5vx2 power supply coming to the board or not. Maybe problem with X'former. You've to check it thoroughly.
     
  7. takne007

    takne007 New Member

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    the bat is made in china.no guarantee.pls tell me how to check the transformer.
     
  8. mneary

    mneary New Member

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    2SD965 is a bipolar junction transistor. You can check it with an ohm meter. Scan this forum for the method.
     
  9. takne007

    takne007 New Member

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    could some one tell me the equivalent of 2SD 965 transistor? there is a transformer(driver transformer i think) in the bat. how to check it? where can i find them?
     
  10. mneary

    mneary New Member

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    Where you can find them depends a lot on your location and your resources.
     
  11. takne007

    takne007 New Member

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    i live in India.
    I have tested the transistor using digital multimeter in diode testing position. voltage between emitter and base is 1.05v and between collector and base is 0.65v. what does it mean that the transistor is bad?
     
  12. takne007

    takne007 New Member

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    for the second time of requesting, what is the replacement for 2SD 965 TRANSISTOR?
     
  13. mneary

    mneary New Member

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    That means the transistor is probably good.

    Not knowing the exact circuit, if a TIP31 fits (I know it is bigger) I would try it. The gain is not the same but the circuit is probably a blocking oscillator and wouldn't care.

    I don't know what transistors are commonly available in your town, but now that you have said you are in India, perhaps one of the forum members who can help will speak.
     
  14. takne007

    takne007 New Member

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    so, the transistor is good.then,please explain,why it is showing 1v between emitter and base,instead of .65 volts drop. may be the problem with the transformer. pls tell how to check it.
     
  15. mneary

    mneary New Member

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    I said the transistor is probably good. With some transistors 1.0V is close enough to 0.65V, others it is not. Also check between E and C.

    To check the transformer, identify the windings and check continuity. This is probably fruitless because the problem could be high voltage arcs that only appear when it is trying to operate.

    To proceed further you probably need to reverse engineer the circuit. By this time I would be buying a new one and taking this one to e-waste disposal. But that's just me.
     
  16. audioguru

    audioguru Well-Known Member Most Helpful Member

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    Look at Mosquito Repeller in Google. Those ultrasonic noise makers do not repel mosquitoes. Your government needs to put larvacide in every pond and rain catch basin like mine did. Now all the mosquitoes and the bats that ate them are gone.
     
  17. mneary

    mneary New Member

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    Uncle $crooge, look at Mosquito Racket in Google. It's a zapper in a tennis racket that you wave at mosquitoes. Equally pointless, but a lot more fun.
     
  18. audioguru

    audioguru Well-Known Member Most Helpful Member

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    The history of the extremely cheap Mosquito Racket zapper shows that they either do not work or they fail in a few days.
     
  19. Sceadwian

    Sceadwian Banned

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    For every one you kill 9 others will bite you anyways.
     
  20. takne007

    takne007 New Member

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    i use a liquid mosquito repellant. my goal is only to study and understand the circuit. i want to turn that thing into a stungun, with some multiplier circuits of course.
     
  21. Hayato

    Hayato Member

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    Multipliers circuitry are very unefficient and have very high impedance output.

    You racket have a very low current output and if you add a a multiplier circuit it will become useless.
     

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