Re: Transitor/ESR tester dead
Right I agree.
Transitor/ESR tester dead
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Re: Transitor/ESR tester dead
the regulator should have 5v coming out - start with that!Leave a comment:
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Re: Transitor/ESR tester dead
So pin7 and pin1 of the big chip should be at +5 volt. ISP pin5 is also connected.Leave a comment:
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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.Leave a comment:
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Re: Transitor/ESR tester dead
The schematic is in the PDF file.
Stj, you mean the transistor to the left of the regulator?Leave a comment:
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Re: Transitor/ESR tester dead
battery power goes through the transistor top-right.
it's similar to the schematic but the diode is missing.Leave a comment:
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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.Leave a comment:
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Transitor/ESR tester dead
Starting a new thread about this that began in my Korg Polysix synthesizer thread in Audio forum...
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*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
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?Tags: None
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