Help identifying transistors

Discussion in 'Electronics Resources' started by Robert Dorr, Jun 20, 2015.

  1. Robert Dorr

    Thread Starter New Member

    Apr 6, 2015
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    I need some identifying a couple of transistors. They are surface mount and one is marked "2F U" and the other is marked "1P V". I'm pretty sure they are both small signal transistors and one is NPN and the other is PNP. Any assistance would be much appreciated.

    Thanks,

    Bob
    WA7ZQR
     
  2. crutschow

    Expert

    Mar 14, 2008
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    From your info, it's only a guess as to what they are.
    Do you have any information on the circuit they are in?
     
  3. Robert Dorr

    Thread Starter New Member

    Apr 6, 2015
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    The equipment it is in is an Ortec Ace Mate 925 Scint Bias Amplifier. It's used for Scintillation Probes and Multi Channel Analyzers. The transistor package is a SMD SOT-23. I have done some further looking and I think the important part of the ID that I have is the "2F" and the "1P". It looks like the "2F" is equivalent to a 2N2222 NPN and the "1P" is equivalent to a 2N2907 PNP. What do you think?

    Bob
    WA7ZQR
     
  4. Robert Dorr

    Thread Starter New Member

    Apr 6, 2015
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    And I forgot to mention, it was made in approximately 1990.

    Bob
    WA7ZQR
     
  5. crutschow

    Expert

    Mar 14, 2008
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    It still seems mostly a guess.
    Are those devices bad? If so, how do you know?
     
  6. Robert Dorr

    Thread Starter New Member

    Apr 6, 2015
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    Yes they are bad. One of the "2F" transistors has a burn hole through it. One of the "1P" transistors passes the standard transistor junction test, about .65 volts across each junction when forward biased. the other "1P" measures about 2 ohms between emitter and base and the other "2F" transistor has about .3 volts across the junctions either forward or reversed biased. So I think I may have one good transistor out of the 4. So I'm just going to replace them all just in case.
     
  7. takao21203

    Distinguished Member

    Apr 28, 2012
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    unless its a high voltage or HF circuit almost any transistor will do probably.
     
  8. bertus

    Administrator

    Apr 5, 2008
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  9. Robert Dorr

    Thread Starter New Member

    Apr 6, 2015
    9
    1
    Thanks for all of the information. It looks like my guess was correct, the "2F" is equivalent to a 2N2222 and the "1P" is equivalent to a 2N2907. I've ordered replacements from Mouser. I'll see how the repair goes. Again, thanks for the help.

    Bob
    WA7ZQR
     
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