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Everything posted by jarmund

  1. Does anyone know of anyone gives free samples on transistors as well? I am in need of some 2N3904/3906 or BC547/557, and buying them would cost me way too much, since the shops charges insane prices to ship it to me :'(
  2. Hiya. There are two things i need some help with, and they both involve PCB 1. I am fixing an external souncard, where the USB-connector (female) has been torn off. The thing is that I wouldn't know how to go about replacing it. I've removed the old one, however, the place on the PCB where it used to be is so small that i dont know how to do this with the tool i have availible. The thing is that there are 4 wires that needs to connect to each separate points on an area of less than 1 square cm. Which tools should i use for this? Any tips/tricks i should know about? 2. For a different project i am currently working on, i need to build atleast two PCBs, since size and wight is critical. Anyhoo... i dont have a clue of how to do it; I've made the layout and such, so what im askin is: Where do i go from here, to turn the design into an actually (working) PCB? What do i need? What are the things that needs to be done? Does anyone know of a good guide out there? -Thanks
  3. It looks nice, but im no good at serial data, so to use that one, i would need someone to explain how i convert 8 bits in series to 8 parallell bits.. thanks
  4. Hi.. just for the hell of it, im building a small robot with an arm which will be placed on my office desk to allow me to do various tasks while im not there. Its mostly for fun, but since im often connected to my PC from home instead of going to the office, it would come in handy for things like changing the CD. The robot itself isn't a problem, but the thing is that i would preferr if there were no wires between the PC and the bot, so what i could use some suggestions on is how it should communicate with the PC? A parralell port would be fine, since I only need to control 8 bits, however.. no wires, please ;) Do you have suggestions on some sort of wireless communication that is both easy and cheap to implement on both the PC and the bot? Only one-way communication is needed. The transmitting range im talking about is 2 metres at max, and the bot is running on 9V.. Thanks
  5. What do you recommend for transmitting? VHF?
  6. I have a webcamera which is connected to a 7.2V DC source, and i need to transmit the data from this camera to a PC. The range can be up to 1 kilometer away. What is the best way to do this? Does the communication have to be two-way, or is a transmitter by the camera enhough?
  7. If i've understood your problem correctly, this can be solved easily by using the audio output combined with a rectifier and a capacitor. after that, feed it through a transistor to make sure that you get up to five volts (Collector-Emitter voltage can be pulled from the parallel port). To adjust the voltage, simply adjust the amplitude of the sound you are playing.
  8. I'm looking for 'the best' software to use with electronic circuits. I currently use CircuitMaker, since it allows me to simulate electronics, but on the downside is that the simulation is very limited, and so is the list of components. Does anyone have any recommendations?
  9. Why stock up before they only make without Pb? What makes soldering wire with pb better? (just wondering, if i should start stockpiling and hoarding myself ;) )
  10. You could combine two ore more capacitors to get the desired value. If you put them in parallel, C = C1 + C2 + C3... If you put them in serial: 1
  11. I highly recomend Opera. I've encountered no bugs at all, and all sites (apart from one) i've visited have been rendered properly. It's also alot more convenient built in many ways. You should check it out..
  12. Actually, the input is not a human voice, it will be from a signal generator to make sure the frequency is exactly the ones desired.
  13. As a part of a project i need some sort of frequency detection. Input will be with a microphone, and output would be a digital signal based on the input frequency. For example, if input is 440Hz, a series of ICs would output the binary value 0001. How would one accomplish this? Is there a some sort IC that outputs the frequency in binary availible. If it is relevant, i am building a digital circuit that is supposed to react differently on different sine-wave sounds in the area of aprox 300 - 10000Hz. It does not have to be too acurate, as long as it makes the circuit react differently on atleast 10 different notes.
  14. I used to do both, now im just a musician
  15. Yes, found them. thanks alot :D
  16. I guess you've already checked this, since it is one of the first things i learned about sound engineering: Signal cables and electrical cables should be atleast 20cm apart from eachother, and if they absolutely have to cross eachother, do it at 90 degrees. Checking the ground connection would be a good idea as well. However, if you cant find a solution, you could EQ most of it away
  17. If you need a small capacitor, and you cant find one with the right value, do it the easy (and cheap) way: make it yourself. And it looks alot cooler to :D This consists of paper (regular A4 I found on the floor), some isolating aluminium i pulled out of a cable, the copper from that cable. Tools needed: A Hammer The construction is quite simple... rip the paper into stripes a little bigger than the aluminium foil (the aluminium foil should be aprox 5x20 cm). You should now have two stripes of paper, and two out of aluminium, lay them on top of eachother so that it is alternate paper/aluminium/paper/aluminium. Place a piece of copper on the aluminium on one end, and roll the thing together with the piece of copper in the middle. when you've done that, tie another piece of around it, so that it touches the outmost aluminium-piece (remove some of the outter paper, if needed). Then hammer the thing a little bit, so that it becomes semi-flat (dont hammer too much, as this will tear the paper, thus destroying the capacitor). Below is a picture of the first one i made this way. I made one that had 200nF, but unfortunately i didnt have a camera at that time.
  18. I can draw up to 32 amperes from the 220V (ill just parallel two 16A fuses)
  19. All of us who like the smell of soldering iron better than flowers, who likes a small electric shock better than a nice massage, who would rather go to an electronics-store than go to the bar, and who thinks 1024 is such a nice round number (ok, im probably just talking about myself, again..) has a favourite field within electronics. Which is yours? Which do you want to learn more about? Which do think everyone else should know more about?
  20. In one of the schematics under 'prosjects' (15W FM Transmitter to be precice), a BLY88C transistor is listed under parts.. however, this has proven hard to find where i am (norway).. so is there an alternative that would work just as well?
  21. Me and a friend is currently working on a cool prosject, however, we need a monstrous powersupply.. atleast 30kV DC (preferrably around 50kV). The input voltage is 220V AC. When it comes to amperes, I only need 1A at max. I've searched for good scematics out there, but i was unable to find any. So.. do any of you know of any good schematics for a safe design, or could someone take the time to draw me one? (Safe = You survive as long as you stay atleast 1 meter away from it :))
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