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Circuit not working, transistor heating up? Answered

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Hey guys, I made this circuit (diagram attached) but it isn't working. There is no output voltage and the transistor is heating up like crazy.

Some differences in my circuit:

1- I got my transformer from an LED bulb and not a camera.
2-I'm feeding it 3v for testing.
3-The NPN transistor I used is 2N3904.
4-Im using 2 100 ohm resistors in series instead of one 220 ohm.
5-I didnt attach a potentiometer,
6-I couldnt find a capacitor like that so I used a polyster 400v 473J capacitor.
7-My diode is not a schottkey one but a 1N4007 diode.

I double checked al my connections and there are no shorts.

14 Replies

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shahryar.adil.3 (author)2016-02-29

Well turns out the transistor was heating because it was shorted. Thats fixed, but the circuit still isnt wortking :/ I can prove the ohm ratings or whatever of the transformer if you need it

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iceng (author)shahryar.adil.32016-03-05

Just two of ten possible configurations.

Disconnect the XFMR (transformer) and Please measure ohms between pins

1-2,6-5,6-4,6-3,5-4,5-3,4-3,1-6,1-5,1-4,1-3,2-6,2-5,2-4,2-3 and your meter shorted probes to each other...

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user

You probably need a new transistor, Check eBay

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user

We still a) need to know what you expect this to do

b) we need to see your actual build.

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user

Kind of a shocker. https://www.instructables.com/id/How-to-build-the-worlds-smallest-shocker-wLED/ That but with a 6 pin transformer.

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user

Therein lies a problem, if your not using the identical components then whether the circuit works may be a gambol. electronics is like that, sometimes you can get away with it and some times not.

In this circuit the transformer is critical to it's operation. Problem solved I think. get the right components.

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Yonatan24 (author)2016-03-05

You probably need a new transistor, Check eBay

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steveastrouk (author)2016-02-27

What on earth is it supposed to do ? It looks like a random assembly of parts.

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-max- (author)steveastrouk2016-02-27

I see what looks like a classic self oscillating transistor circuit that generates a few huntred volts.

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steveastrouk (author)-max-2016-02-27

Anywhere near that little transistor ? Really ?

And how is the base of the transistor connected ?

What is the picture of the camera for ?

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user

I think the camera symbolizes where this circuit came from, or possibly what it is intended for, specifically, for charging the capacitor for the camera's flash.

Yes. I also noticed this "circuit diagram" is lacking in useful information, like details about the {emitter, base, collector} connections to the transistor, and also the windings of the transformer.

At the same time, this diagram maybe has information that is useless, or redundant, like the words "Red Red Brown Gold". Hmmm...

Well, whatever it is, I don't want to step in it.

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-max- (author)steveastrouk2016-02-27

"Across that little transistor ? Really ? And how is the base of the transistor connected ?How do we get a transformer capable of that from an LED driver ?"

You're right, and I pointed those flaws out in my answer to the question. I guess you deleted this comment already though since you saw my answer after replying lol.

I assume the LED driver was driving something like 30-50 LEDs in series from AC. I have a decommissioned large LED streetlight that uses something like 48 CREE XR-E LEDs and the inverter had rated output of 100-400V @ 350mA. Assuming this is a constant current driver. Assuming the setup is something similar. Even if it is not rated for it, I find it pretty easy to get a few hundred volts out of a even audio transformers due to the flyback princible.

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-max- (author)-max-2016-02-27

Huh, now your comment appears. Instructables is so slow...

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rickharris (author)steveastrouk2016-02-27

Crystal ball says it's supposed to charge the cap up to 400 volts.

But I assume this isn't what was built. Be nice to see that.

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