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quantum

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Everything posted by quantum

  1. Thank you for your effort. So I suppose that any frequency will not penetrate the photocell. So how 'bout a particle generator, is there such a thing, I don't know.
  2. Would anyone have such a clue on how to turn off the light-sensitive street lights? Light toches the photoresistor of the street light and the light goes off and vise versa. Light, I assume, is made up of waves and particles, so would any other type of frequency turn the light off? It is complete nonsense when those street lights burn during the night and have their streaks of light burst into your house unbiddenly. >:( >:(
  3. quantum

    Inductor

    Cdonke, 1. The factors that determine the inductance is number of turns, area of the coil, length of the coil, and the core of the material used. Your description doesn't include the core material, so the measurements cannot be determined. 2. You can calculate the inductance in henrys (L), after Joseph Henry. The formula is L= N* x A x u/ l. L is the inductance, in henrys, N is number of turns ( the "*" is meant for the number of turns to be squared). Times the cross-sectional area, in square meters. Times permabilty of the core. Divided by the length of the core, in meters. 3. I guess you can replace it with another kind of inductor, with same measurement of henrys though, but not for a resistor. 4. Yes, the distances between each coil does matter.
  4. This transistor I found in a light sensitive night-light. The whole circuit has only three parts; resistor, photoresistor, and a transistor. I would like a datasheet for the transistor,which printed on the transistor is 43536 T 107 (the "T" is like a smbol). I would greatly appreciate it!
  5. AVRFreakMan, I modifyed it to the correct spelling. Thank you for your knowledge on a limited supply of curent for the mic., thus to put a resistor in series. However, you didn't answer my question on why there is a input lead.
  6. This project here, I have multiple questions. http://www.electronics-lab.com/projects/rf/018/index.html First off, the microphone on the left of the schematic. The V+ I'm assuming, is where the positive terminal of the battery is to be connected indirectly. The ground smbol is for the negative terminal of the battery to connect to the mic. also. My question for you is what are you suppose to do with the input lead of the microphone. Is it just me, or are there some microphones with three leads coming out of them? I am pretty there are not ones like that, of course. I've seen that the input is just the V+. Is that true, or is that pish posh? Another question, what does CB in CB transmitter represents.
  7. Thanks guys! :) I took Audioguru's advice and added a 10uF capacitor to to pins 1 and 8. That worked at pretty well. I also tried a 100uF capacitor, but it was just too loud/annoying. ;D I have thought of the Nightrider circuit, and it seems pretty neat and catchy. Although I hope Radio Shack has the ICs, because thats what they lack is variety of ICs. I may just order offline. ;)
  8. Audioguru, I have trumendous news. I finally built the amplifier circuit since I found out all my answers. And my confindience of it working was 1 to 10 (least confideance), but I tryed. And what would you know, it work. I amplifyed an answering machine. The potentiometer work extremly well. However it wasen't the loudest thing in the world, but it sure made the sound louder than it was oringinally!!!!!!!!!!!! ;D :D ;) :) This circuit I made was the lowest amplifying circuit of all of them, but it was sure loud enough to be satisfing whenever the phone answering man sayed you have no mail. ;D
  9. Hello Audioguru, You say to connect the negative terminal of the battery to the signal source. Is that the input source?
  10. I see your point Audioguru, I accidently switched the terms around. What I would like to do is just amplify a speaker. Which is amplifying the input of the speaker signals, because speakers don't give off much output if not at all.(Correct)? I also added that I wanted to amplify a (electret) microphone. Which now I know is to preamplify the output signal of the microphone instead of the other way around. Are you suppose to add grounding points of leads 3,4, and the two of lead 5 together and link them to the negative terminal of the battery of the schematic: amplifier with gain=20.
  11. I plan to build my own audio amplifier circuit using a LM386 chip. However, I am in need of assistance. Here is the datasheet for the LM386 chip. http://www.national.com/ds/LM/LM386.pdf First off, I would just like to amplify the output signal of a speaker. If it is possible, I would like to amplify the input signal of, say a microphone. Leads 1 & 8 are the gain pins, what would I do with those pins? Lead 2 & 3 are the input pins, so would I the oringinal speaker wires? Lead 4 is the ground pin, what would I do with that lead? Should I just attach it to the negative terminal end of a battery? Lead 6, I'm assuming,is the voltage source (Vs). If so, is it the positive terminal of the voltage source? If so, which is the lead to the negative terminal of the voltage source. Lead 5, I'm assuming, is the voltage output pin, for what would that be. And finally, lead 7 is the bypass, for what would that be for.
  12. Well, so I can make schematics from stuff I take apart. :D Then frame the shematic! ;D I wouldn't won't to brake it open, because I already kno what is in it. But I have broken into a silicon chip before I knew how they work.
  13. Audioguru, I see your point, however I have heard about capcitors that filter, such as in a rectifier (perhaps ;D), and also a tuning a radio with a variable capcitor. I know that if a capcitor is attach to an AC outlet, the capcitor charges and discharges rapidly because of the alternating current. Does this concept work with filtering radio interference or is there an entirely different concept?
  14. Kain, I'm now pretty positive it is a surface mount resistor, because I have seen them on the printed side of a circuit board. ;) Thank you for helping :) (I don't like components that I don't know ;D)
  15. Whenever I take apart something, such as radio-control car, the motor is populated with capcitors. About three of 0.01 or 0.1uF ceramic capcitors are attach to the eletric motor. Does anyone know of this reasoning of attaching these capcitors?
  16. What is SMD? ;D I am pretty sure it is a capcitor, and they usaully range from 16 to 1600 picofarads (which I just read about). Maybe it is a resistor, hence the labeling of "R". Thanks!
  17. I have another fishy component. It is extremly small. The home page of this website has a background graphic of a pcb at the top-right corner. There is a IC chip and right below and above to the right is a bunch of really small black squares. When I look at a pcb, it labels the small black square R** .The * stands for the number of the sqaure, just like a resistor. Sure, if I only knew how to copy a picture on to this reply, it would be much easier. If anyone knows how to do this, I would appreciate it. ;D
  18. Thanks Kain! :D I think thats what it is. I frogot to add in my question that I took it apart and there was some kind of "netting". Maybe that is the quartz. :) And to add, its about 1/8 a inch in width. ;) Do you know the shematic symbol? ;D
  19. My question is that on devices like radio controls, there is a silver component that is about 1 cm. tall and has the numbering of the radio freq. that it is supposedly to give out (such as 27.145MHZ). Does anyone know of this device? :)
  20. The physics of semi-conductors takes a lot of practice to understand fully. One concept I want to learn is the subject Newtonian. If anyone has some information on this (Newtonian) subject, I would be greatly appreciated. :)
  21. Audioguru, I was using a 9 volt battery so I will try adding the diode. I have 4001 diodes, and I'm wondering if they would work. I know how diodes work, but what do the numbers on them mean?
  22. I heard that grounding the wire to your faucet is good idea for grounding. No matter where the grounding symbols are on the schematic, you connect all of them together, then ground them? :o
  23. MP, I have a question relating to microcontrollers. I have a vague definition of relays. I know that they have to do with the binary system, however whats confusing me is I heard they were transducers. ??? Is it just me, or do they produce an electromagnetic field to trigger something? From what I heard.
  24. MP Thats what thinking about, Hotwaterwizard's schematics. If you or anyone else have blinking LEDs with microcontrollers, that would be great ;D. I am just getting into plcs, and microcontrollers. One other thing. The schematic that Hotwaterwizard post that involved two NPN trasistor I actually built with the exact supplies it contained. However, the LEDs did not blink alternately. One blinked every second or so and the other every 30 millisecond or so. Is that suppose to happen, or am I doing something wrong? ???
  25. What do the terms mean? SPICE, IBIS, & THRESHOLD. ???
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