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how do i read this stuff? Answered

i have played around with motors hooked up to batteries and thats about it. i know a few things about electronics but i am looking to do some projects that involve circuits. i dont know how to read it when it is in a drawing. it looks to confusing to attempt. all those lines crossing and all those symbols. i have a book called electronics for dummys but it doesnt give to much detail. does anyone know how to read this stuff and can help me? is there any sights on the internet that would help me. remember i am pretty newbish. so it needs to be in newbish form. lol. the drawing below is from a powersupply that i would like to build. thanks ~Josh

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gmoon (author)2007-12-27

Excellent explanation from 'guyfrom7up.'

I'd like to add a little more 'filler:'

The left (input) side is DC voltage, 3V to 40V. A DC wall-wart will work fine. If you're using a 'bare' transformer as the source, you'll need a bridge and a filter cap, too (convert AC to DC.)

You'll need to 'feed' it more volts than you plan to use--if you want a range from 3V to 12V, 15V for the input should be fine.

LM317 wikipedia link, this has datasheets, too (might be a bit confusing, but you need to start sometime.)

One more thing: the bottom (GND line) is often not physically connected in schematics. Rather, it's represented by a GND symbol....

Another one more thing: When multiple components are connected together to the same line (VO on the schematic), it generally doesn't matter where they are connected. I.E., D1 could be connected to the right of D2--it's all the same, electrically...

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Goodhart (author)gmoon2007-12-27

A good example of what Gmoon is speaking of concerning the ground line is on the following power supply schematic:

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gmoon (author)Goodhart2007-12-27

Goodhart's schematic also illustrates a transformer as the source (input.) However, it's a multi-tap transformer, and you won't require that type. If that doesn't make any sense, don't worry. Try to find a DC source first. If you must use a transformer, ask here, and someone will explain how to hook one up to your power regulator circuit...

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Goodhart (author)gmoon2007-12-28

No, sorry for the confusion, I was just illustrating the Ground line being shown with the ground symbol rather then a straight line.

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GorillazMiko (author)2007-12-27

R2 is Resistor 1 and D2 is Diode 2. So R2-D2 from Star Wars is "Resistor 1-Diode 1". Just kidding. If you google up "schematic symbols" then you'll get a bunch of sites, and they'll show symbols used in schematics.. and you can figure it out, it's pretty easy.

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guyfrom7up (author)whatsisface2007-12-28

yeah, really, lol i'm not being sarcastic

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guyfrom7up (author)2007-12-28

no problem, I'm glad to help, makes you feel all good and special inside, lol.

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guyfrom7up (author)2007-12-27

in some parts of the schematic 3 parts are connected together, in this schematic, nothing's overlapping, so all the greens are touching as they appear. where ever there's a green dot, those too wires are connected. For example: Pin2 of the LM317T is connected to R1, D1, D2, C2, and the output. usually in a diagram a dot means that the wires (technically called nets when using Printed Circuit Boards) are connected. no dot means that they are not. In other schematics there might be a slight curve, kind of like a jump across intersecting wires that arn't connected, and everything else is connected, just as a dot was before, just no dot. Pm me if you have anymore questions that don't really fit anywhere.

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Goodhart (author)2007-12-26

A few places to look at: Reading schematics guide

for help, and also another source...

Like reading a map, it is only a matter of learning the symbols:

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Goodhart (author)Goodhart2007-12-27

It just takes a little practice

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guyfrom7up (author)2007-12-26

Electronics for dummies is the worst electronic book ever, but it was my first electronic book. This is called a schematic and it tells how to hook up stuff. In this case whenever wires are connected there are little green balls, wire are green. The wires could also be a circuitboard. C1, 2 paralel lines mean a bipolar capacitor, usually ceramic. it's value is 0.1uF. S1 is a switch, pretty slef explanitoy D1 is a diode, in this case the 1n4001. 1n4001 is a pretty common diode, you can even get it at radioshack. D2 is another diode, except it's the 1n4004, you can buy this at the shack too A nice thing about diodes in schematics is that if you want it to conduct, make it point from + to -, like this +--I>-- minus IC1 is the integrtated chip lm317, which is a variable voltage regulator. R1 is a resistor with a value of 560 ohms R2 is a potentiometer with a max value of 0.5k ohms (or 500 ohms). Make sure you get a potentiometer that is linear, not audio. C2 is a polarized capacitor, usually electrolyte, but it could be tantalum. The flat bar always represents the +. It is 10uF. Anymore questions? Are you building a laser power supply, or is just an adjustable? make sure all of the capacitors can handle the voltage. Make sure the resistors can handle the watts.

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Goodhart (author)guyfrom7up2007-12-26

If I remember correctly the 1N4001 is a one amp / 50 v GP rectifier diode and the 1N4004 is a one amp / 1000 v. GP rectifier diode.

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guyfrom7up (author)Goodhart2007-12-26

1n4001 is one amp/ 50volt like you said 1n4004 I think is 400volt at 1 amp, I think, I can't remember.

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Goodhart (author)guyfrom7up2007-12-26

Actually I am not so sure it is a good idea to have "0" ohms from ADJ to ground (lowest setting on the Pot). A small resistor in between would circumvent some potential problems, don't you think?

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guyfrom7up (author)Goodhart2007-12-27

probably, just for saftey

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guyfrom7up (author)2007-12-26

Oh, and that zigzag thing at the bottom is a potentiometer, it's basically a variable resisitor, whenever you crank anything on any electronics, it's usually a potentiometer. R2 is a potentiometer with a max value of 0.5k ohms (or 500 ohms). Make sure you get a potentiometer that is linear, not audio. Thee difference between audio and linear is this: Audio- The resistance changes dramatically, te resistance is in a wierd way because of the way we hear things, I'm not good at explaining audio. If you were turing the dial at a constant place it'd be like 1 2 4 8 16 32 64 ohms, not linear linear- it's a constant change, if dialing: 1 2 3 4 5 6 7 8 9 10 ohms a 100k ohm potentiometer's minimum value is 0 ohms, and max value 100k ohms, just as an example for how to buy them and looking at there value.

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guyfrom7up (author)2007-12-26

also asking a bunch on the forums, if you have any questions that you think are super simple you can just pm me, I'll know the answer most of the time. The key to electronics is not to skim, when reading the books READ THE FORMULAS, don't just skip over them also look at the pictures. If you see a page with a whole bunch of schematic symbols and what they mean right nexst to them right them all down 2 or 3 times, after that it'll be pounded in your head, I did this.

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guyfrom7up (author)2007-12-26

Long story short there's a club at my school called tsa where it's kind of like teched. Me and my friend desided we were going to build a fully functional android robot, but after doing a lot of study realised it didn't apply to any of the challenges. I read a couple of books over the summer. Best books to read to learn: Teach yourself electricity and electronics, the fourth edition by Gibilisco- A pretty good book, tells you everything you need to know. In order for this book to work you MUST read, NOT skim the chapters. A nice thing about it is that there's little test at the end of each chapter so you really know if you know that you know it, lol. Robot builders bonanza- pretty good, doesn't go into super depth into everythingt as the first book i mentioned, but it's easier to read. Practical electronics for inventors- Excelent book, everything you need to know about anything. Teaches really well about transistors (I could never get how to use them until I read this book) and has excelent water analogies for everything. In conclusion: Teach yourself electronics- good if you want to know everything Robot builders- ok overall info, pretty good if you want to build robots practical electronics- My favorite, but it doesn't have some stuff that teach yourself has. If you could only buy one, I'd pick practical electronics for inventors, it's blue and has a lightbulb on the front. It's pretty cheap on amazon

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