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  1. J

    low battery alarm

    Well from what I can see when the first transistor turns off the voltage to the base of the second transistor goes high and turns that transistor on. This allows the base of the third transistor to go low which allows it to conduct, since it is a PNP type transistor. The 1u capacitor is what...
  2. J

    Disassembling an old oscilloscope

    the CRT itself will hold a charge, like a capacitor. The suction cup on the CRT, underneath that is a wire. You should short that to ground.
  3. J

    Ideas and Feedback

    Great reading material. I appreciate it.
  4. J

    Disassembling an old oscilloscope

    I wouldn't worry about my hand getting blown off, I would be more concerned with a direct shock across my heart. Basic electrical safety should always be on the mind. Other then that, does this thing have a CRT? my guess is yes since you say it's old. That could potentially deal the most...
  5. J

    Free Engery

    when it comes to free energy, breaking the laws of physics isn't gonna be easy. I apologize if it sounded condescending, but it's a hard fact that most people should start accepting. It's not like the concept is new and there is plenty of evidence to show that it will not work already. Which is...
  6. J

    Request for a book title on how electrons are stored to create binary code.

    No, in fact the microsoft kernel uses C/C++ and the linux kernel is in pure C. The linux kernel is freely downloadable, so if you just want to stare at code then find your way to www.kernel.org and start browsing the git repository. Again Hex code is just machine code interpreted into a more...
  7. J

    AC hedge trimmer --> DC generator

    Well if I was you. I would first check to see that if the shaft of the motor is turned I was getting some sort of AC voltage out of it. As for the rectifier, you would only need a half wave bridge rectifier (2 diodes). I don't know enough to say what the output would be from the motor
  8. J

    Optoisolated Triac Water Heater Controller

    Now, in the schematic you have the thermistor resistance at 100k ohms at 25C. That means the negative input has 9.5~ volts. The two resistances make a simple voltage dividing network. Vout = (R2/R1+R2)*Vin http://en.wikipedia.org/wiki/Voltage_divider In other words, if R2 is Greater then R1 the...
  9. J

    Amplifying DC voltage

    Thats correct. My only guess is to turn the DC to AC step it up and then rectify it back I suppose. One of the resident experts will be along to voice in. Does your project have to use a battery as the voltage source?
  10. J

    Amplifying DC voltage

    I thought the only way to increase Voltage past the max Vin was to use a step-up transformer.
  11. J

    30kV Power Supply

    I think this should be a good warning for you. I understand that circuit and I don't see any parts there that are very special enough that you couldn't find replacements for. I consider myself pretty 'new' to this whole electronics thing, but even understanding that schematic makes me hesitant...
  12. J

    Request for a book title on how electrons are stored to create binary code.

    Are you trying to understand how Memory works? You seem to make a few assumptions in your first post that really ain't true. Capacitors don't 'lock' in binary code and I don't think you'll ever see a relay in a digital computer that is of any use other then to show it can be done for various...
  13. J

    Ideas and Feedback

    I second this, I would really enjoy reading more tutorials and examples of common uses of these parts. I never get tired of learning as much as I can about anything electric and electronic. off the top of my head, "impedance" seems to be a word I can not grasp the full of. ;) Lets hope more...
  14. J

    Free Engery

    If free energy was as simple as putting an alternator on a car that produced more amps then it consumed, we'd already be doing it.
  15. J

    How to use transistors to amplify current.

    I'm with mitch. Your design is flawed and if you change the design to a proper one you will lose some brightness. Maybe the internal resistance of the battery is the only thing that has saved your LED's thus far.
  16. J

    How to use transistors to amplify current.

    In series, the voltage drop across all components will add up to Vin and the current remains the same across all components. In parallel, the voltage across each component is equal to Vin, and the current across each component is a fraction of the total current draw, Iin Absolutely
  17. J

    How to use transistors to amplify current.

    Current has to come from some source, in your case that source is the battery. So I don't see how using a current amplifying circuit will help. You can't just materialize current out of thin air.
  18. J

    new here

    Source code - code that is written by you to control a process. It can be written in any number of programming languages. High level programming language - C, C++, Lisp, Basic as apposed to a low level language like ASM. Assembler - is like a compiler, except it is used to translate ASM into...
  19. J

    Need help with circuit

    You misunderstood what I was saying, i'll take the blame for that. I should have been more precise. You hook the positive part of the battery to the positive lead on the LED, then hook the negative lead from the LED to the collector. The schematic shows the LED is in series. Then keep the...
  20. J

    Need help with circuit

    http://en.wikipedia.org/wiki/Parasitic_capacitance I didn't know what parasitic capacitance was either, but could the above be why this circuit works? Just guessing here, but wouldn't you touching the base make you act as a resistance activating the transistor? Laplace may be the more correct...
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