Transitor/ESR tester dead

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  • keeney123
    replied
    Re: Transitor/ESR tester dead

    Originally posted by stj
    the regulator should have 5v coming out - start with that!
    Right I agree.

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  • stj
    replied
    Re: Transitor/ESR tester dead

    the regulator should have 5v coming out - start with that!

    Leave a comment:


  • keeney123
    replied
    Re: Transitor/ESR tester dead

    So pin7 and pin1 of the big chip should be at +5 volt. ISP pin5 is also connected.

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  • stj
    replied
    Re: Transitor/ESR tester dead

    this is probably it.
    Attached Files

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  • keeney123
    replied
    Re: Transitor/ESR tester dead

    Thank Steve. So you have a plug in "worts" if I spelled that right and a 9 volt battery. I imagine when its plug in it disconnects the battery. What are the symptoms? Does it not have a test button?
    Last edited by keeney123; 09-11-2015, 09:41 PM.

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  • stj
    replied
    Re: Transitor/ESR tester dead

    yes, just follow the track from the red wire.

    you could run a fine wire from the red cable to the input on the regulator for a quick test.
    Last edited by stj; 09-11-2015, 09:35 PM.

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  • SteveNielsen
    replied
    Re: Transitor/ESR tester dead

    The schematic is in the PDF file.

    Stj, you mean the transistor to the left of the regulator?

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  • keeney123
    replied
    Re: Transitor/ESR tester dead

    Where is the Schematic?

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  • stj
    replied
    Re: Transitor/ESR tester dead

    battery power goes through the transistor top-right.
    it's similar to the schematic but the diode is missing.

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  • vinceroger69
    replied
    Re: Transitor/ESR tester dead

    hi i have the same tester here any measurements you need just ask on the regulator i have 9.37 in 4.99 out im running off a 9volt battery is your dc power supply still giving the correct output voltage you have probably already checked this though.
    Last edited by vinceroger69; 09-11-2015, 11:39 AM.

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  • SteveNielsen
    started a topic Transitor/ESR tester dead

    Transitor/ESR tester dead

    Starting a new thread about this that began in my Korg Polysix synthesizer thread in Audio forum...

    Originally posted by SteveNielsen
    That's what I'm in the process of doing. Unfortunately I will have to spend money so it's going to wait a little while. My Chinese transistor/etc tester just died too. At least I can still measure capacitance on my DMM.
    Originally posted by stj
    seriously? there's hardly anything to die on them!
    you did discharge the caps you wanted to test i hope - the testers are 3.3v
    Originally posted by SteveNielsen
    I am very good about discharging caps before measuring them. I may have missed doing so to the last one. It's usually my habit to discharge but I don't know. However, it failed right after I had re-soldered a test lead to it that the strands were breaking on. It's soldered to a length of solid wire that is soldered to a PCB pad, so I didn't overheat anything or that bit of solid wire would have come loose. Regardless, the little guy won't fire up. Oh well. I've gotten a lot of use out of it. I'll get another when I am able to.

    Edit: it was also running on a regulated DC power supply not a battery, so I suppose a momentary power fluctuation or spike that didn't get filtered out could have killed it but I've been using it that way for months. *shrug*
    Originally posted by stj
    post a foto of the parts-side so i can see the design.
    it may just be a voltage regulator.

    btw, i just ordered this model.
    i chose it because it has a 3pin connector and flyleads.
    http://www.ebay.co.uk/itm/181861030068
    Originally posted by SteveNielsen
    I like that one. I think I want one too.
    Originally posted by Agent24
    That thing looks like it has no input protection, you could well have blown the uC with a charged capacitor.
    Originally posted by stj
    see if that regulator near the battery wires has 9v going in and 5v coming out.
    btw.
    Originally posted by SteveNielsen
    Nope, input on the reg is only 2.4v, output is about 1v.

    Yes, it's a known fact that a charged cap can damage the chip. The manual warns of it.
    Originally posted by stj
    i think your dead tester is just a transistor.
    look at the pdf i linked - page11
    Originally posted by SteveNielsen
    I did look and have questions but I think I ought to start a new thread about this.
    Ok, back to the present.

    Stj page 11 appears to show a mod for the board but not what's there on my board. If I'm mistaken let me know. If you meant the basic schematic then what transistor are you referring to?
    Attached Files

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