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Everything posted by quantum

  1. THanks again for well explainded answers. About that quote, I don't understand why in the world why and how you would put C- B in reverse bias, however, isn't C to B work like a diode and if you had that "diode" in reverse bias it would leak unwanted current, possibly ;D. Now for the last page... 1. for the first graph, top left, don't understand why that have such a graph. Like what is the purpose for showing the C current against C-E voltage. It just seems abstract and I can't realate. 2. So even if the C-E voltage is at 0, there is still current in (or going through, about to go through or having the possibility of going through?) the collector. But I thought that currents mostly lag behnd by say 90 degrees. I'll wait with the other confusing graphs. ???
  2. quantum

    FM Bug?!

    Thanks! It was bugging me not knowing what it is. ;D
  3. Thanks for the answers. I really understand the Vcbo and other similiar stuff. 2nd page... 1. What is cut-off current? 2. How about current gain? 3. What's Hfe, I know that it's current gain smybol of course, but what about the individual letters. 4. What is saturation voltage? 5. I don't undrestand the collector ouput capacitance or why how what, I know nothing about it. Thanks Audioguru.
  4. http://www.datasheetcatalog.com/datasheet/BC/BC548.shtml ( the datasheet for General Purpose Transistor) This site is cram pack with stuff I don't know. I am going through them and asking anything I don't know. All of these questions are on the same page. 1. Under "Features" there is "High Voltage" then goes Vceo. Is that the maximum voltage from the collector to emitter? Also, what is the "o" in Vceo, I am thinking it's voltage or something. 2. Next to "Maximum Rating" is "(Ta=25*C)". The T is obliviously temp., but what is a? 3. For the chart of max. ratings, there is a colomn donated to the Smybol. The fisrs three cells in the Smybol colomn has Vcbo Vceo and Vebo. What is the "o" in it? 4. I don't understand why the rating is neg. in the row Emitter Current. 5. In Junction Temp. what do they mean in Junction or what is the Junction? 6. The chart that holds the drawing of the transistor, under the millimeter colomm, some of the cells have MAX, what would that be? 7. Under the drawings, there is TO-92, I am assuming that it is for the package type.
  5. quantum

    FM Bug?!

    I have heard of a bug, what is it? http://www.electronics-lab.com/projects/rf/002/index.html
  6. Kasamiko, is this item STRG or SRTG? And where and/or how did you come across this item?
  7. I figured out that the fire engine horn uses compressed air to make that sound.
  8. Do any of you guys no how to create a normal sounding sound into a much deeper sound through chips and what not? Thanks in advance, I have a "friend" whose voice is too high, and not deep. ;D
  9. Thanks! I just had a question on the test about a true real life happening consisting of two variables that isn't a function. I was baffled when my teacher said that question would be on the test. It sounded like, what is a function that isn't a function. I got exactly what your saying, meaning if you overshoot, you hurt the child or system. Thanks for your help.
  10. That makes sense. I beginnning to become really familiar about ground and how all neg. terminals are just somewhat nuetral in some way. What about being able to identify transistor only by looking what is printed on it. I made the flashing LED circuit work with your guyes help about the attaching the diodes to it. I changed the res. to make them flash at the rate of which a reseted digital clock blinks. http:// 12:00
  11. What would be a real life function that doesn't pass a vertical line test?
  12. How do you know if a chip/semiconducter is a Ula or custom chip? Would it sometimes be a blob of the material with no written information about?
  13. I want to make a honk but not a beep, a really loud one like fire engine does. Schematics, information, etc. Would for fill my project needs.
  14. Since you say it can only be electronic, its wise you came to this website. What needs to happen is for you to create a small spark, eletrically. This small spark will propably ignite the gases that thingy you sayed was dipped in. And you got yourself a fire. Now into detail on how you should come across this spark is by a fair amount of voltage/amperage. Such as when I was trying to make a spud gun, or gun that shoots stuff with gase(s) ignited, I simple made a small spurt of fire with just hairspray as my "gas" and a voltage around 13 Volts. Aha. All you need is conductive wire and possibly a car battery. The bigger the voltage/amperage, the bigger the spark I assume, so if you can get several 12 volt batteries, or even the electrical outlet, which is awfully dangerous, the better the chance of a spark happening. Now that you have your potential spark, you need a spark gap, which is where the electircal current breaks the dielectric thickness of air. Have the two wires close together and crank the voltage. If nothing happens, theres propably not enough electric current going, so either put the gap of the two wires together or crank up the voltage. If all fails, there are projects you can study and possibly make like the Tesla Coil which produces a high voltage/nice spark gap. And you can and carefully use the AC wall outlet to get that spark going. I'm glad you read this, I needed to get my high voltage lecture out. ;D Ask me for questions.
  15. So in other words, them AAA do not last as long as those AA? ;) :o
  16. http://www.electronics-lab.com/projects/power/014/index.html My questions are from this site. Are all transistor's code labeled on themselves so you can perhaps indentify them on a circuit board? Such as those transistors in that site. What does the term "tordial" mean in this sense? Where do you insert the 6 and 12 volt terminals? I know where the you insert the the positive terminals of each, but where do you put the neg. terminals? Do I just put each negative terminal on the neg. bus line?
  17. If AA and AAA are 1.5 volts, whats the difference?
  18. Do you have a schematic for it? So how long will the "transducer" be on with your creation of 100kilohertz.
  19. Hi Hotwaterwizard, What a Devide? ;D Neat, do you have a schematic for it?
  20. Hi guru, You sayed, So that the amplifier and speaker don't overload, I designed it so that the bass is always the same level. Did you do that with digital means, or by analog. And how long you have been in this area of intrest. Very interesting modification! Question for you, do you have to have a heat sink tool to solder on semiconductors, and what is harmed in the chip if you do that? I have heard of these heatsink on motors, and for circuit components, is there tool plier-like, that sucks up the heat from the solder iron? What is Operational Amplifier {Op}? Is there a website that I could "draw" a schematic. I have one of those really old carry-bag mobile phone, which I took apart. Like you Audioguru, I want to modify it. Would it be possible that I could change it so that it intercepts other frequencies? What range of frequency does these mobile phone give out? From what I see, there is two crystal quartz. The circuit board has almost nothing but smd, and same on ther other side of the board.
  21. People here a lot of the time say "oh, you can get that circuit at this website and right and there but not from knowledge and experience from people like yourselves". Does anyone have a shematic that they made their own, purposely or accidently. I accidently shut my computer down while testing my transmitter. ;D Please explain the process of your schematic and difficulties. Thanks!
  22. Thanks for the information. I haven't been here lately because school has started and I go through phases of intrests, like right now is cosmology and radio control aircraft. I just want to say I haven't disappear on you guys. 'Till next subject. ::)
  23. Thanks for the website, what I want to do is to attach a reciever to my radio control helicopter so I can drop small items from above :D. I think I just might take apart a cheap remotely comtroled car and take it from there.
  24. What I tried to say was that I tried to make the diameter of the laser bigger, which I did. So I suppose what you are saying is that you can't futhor more intesify the laser pointer. Correct?
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