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Everything posted by gogo2520

  1. Hello You can make a square wave oscillator with two npn transistors, two capacitors, four transistors, two leds, and a nine volt battery. The only other part you would need is a battery clip, and if you want to get fancy a project board. Thats an old timer project. they use to take a peace of wood and drive copper nails to were they wanted to solder the components to and wire in the rest. You don't need a ic to flash leds. gogo
  2. Thanks Guys I'm not real good at building power supplies, mine are pretty simple. When I need a good large one I would use a prebuilt by someone who has the right stuff to do it with. I think this fall I am actually going to break down and invest in a oscilloscope and study power supplies along with a lot of stuff. The reason is because I am getting ready to retire and am going to need something to keep me busy, so why not a hobby I enjoy. When I see something I don't understand I tend to ask questions and I might be a little crude about it. Sorry about that. Yes Hero999 if you don't mind please your schematic for the center tap power supply. thanks again gogo
  3. Sorry I don't know were the 18 volts came from the original post shows a 12 volt input. I figured he would use a 12 volt transformer to start with and then use the regulator to lower it. And that would of been (12 - 1) x 1.5 = 16.5W ( 4 degrees x 16.5) + 30 degrees = 96, well under the max allowed temperature. Ya but still hot. gogo
  4. Hello Wounder why the data sheet doesn't say that gogo
  5. Hello t1800 And welcome to the form. A general purpose pnp transistor like the 2N3906 will handle 200mA's. gogo 2N3906.pdf
  6. hello ashishamours The lm317 to 220 package will handle a 1.5amp. If you need more try the lm350 to-3 package that will handle 3 amps. gogo
  7. Hello thavamaran Lot of what you want to do depends on what you want the robot to do. Electric motors will run a lot of things the trick is to get them to stop when you want them to. Most robots use stepper motors or servos because they can be controlled better. Pic microcontrollers can be programed to do a lot of things but there outputs can only handle about 25ma so controlling a electric motor by itself is not going to happen, you would need some kind of driver for what ever motor you use. gogo
  8. Hello green1706 I do not understand what the problem is. You have a LCD monitor connected to what. and what is the monitor is powered? Is this a computer monitor with a software setting problem? gogo
  9. Hello ritaban I found this short tutorial that might help you, gogo PS if you google 8085 microprocessor tutorial, you will find a lot of info 9698563-tutorial-on-8085-microprocessor-architecture-and-programming.pdf
  10. You might try taking your medication. But I got to admit I like the idea of wrapping your car up with aluminum foil. gogo
  11. Hello credits google Digital signal processing and you will find all kind of info and tutorials. gogo
  12. gogo2520

    Re: Relay

    Hello leo Here is a good discription of relays http://www.kpsec.freeuk.com/components/relay.htm Are you talking about double through to single through or do you want to use the relay for high voltage transformer stuff.
  13. Hello Try kicking it harder. gogo
  14. Hello RumbaKing I made one to with the same problem and I think it is because at the time I made it I didn't have the right resisters. I used 5% instead of 1%. Maybe next time I go on a buying frenzy I'll stock up on 1% resistors. gogo
  15. hello Fowkc Hey guy if you just want to see how it works you don't need all this stuff. To etch one board, first is the transfer of the image to the board, once you have that any tank that the board will fit into will do. Hot water from a kitchen sink and a plastic bowl will work. Ferric Chloride dose good at 32C% or 100F%(same I think). When I did my first one I bought a kit for about 14.00 dallors U.S. I got all the stuff ready and put on some plastic gloves and went to work. First thing I did is prewarm the Ferric Chloride in a double bath (plastic bowl inside a plastic bowl) hot water from the sink. Then the board went in, one hand on the inside bowl and rocked it back it back and forth, I could see the stuff work but I though it would happen faster. No it took 15 minutes, but it worked and I didn't need to buy all that stuff. It was my first board and it looks good. Oh I use press_on transfers that came with the kit. I now have a tank set up with the heater and air pump, works much faster, and use a laser iron-on transfer. (office gloss paper). After of about two months of reading and another month of planning I tryed this, I could do it, and now I make my own double sided boards. COOL. Have fun gogo
  16. hello this link might help http://www.sos.mcmaster.ca/publications/386.pdf
  17. Hello charcoaldabs2 Sounds like you did good with the heat gun. My first time I tried to recyle parts from printer boards I tried using a propaine torch. Not a good idea, by the time I got done there wasn't much to do but get a garbage bag out. Now I use a soldering iron with a sucker pump on it, Got that at radio shack, works great on ic's and only cost about 15 bucks. Spring loaded solder suckers work but not very fast. have fun gogo
  18. Hello If you don't have a laser printer, I think the easy way would be to print it out on a inkjet then have it copied with a laser copy machine using office gloss paper.. Inkjet ink is water base and will desolve in water. have fun gogo
  19. hello vkssingh I look at that kit too, the values they used didn't work with my set up. I built it on a breadboard. Got it to work, I have mine set at 200 volts for now, when I tried to set it for 30 volts I couldn't get a consistent reading.Breadboards are noisy lot of bad connections, lot of wire and stuff. I put about 10 10uF cabs on it, that seemed to help. it works just haven't peeked it out yet have fun gogo
  20. Hello syber and welcome. There is a layout discription on the data sheet I would start from there. have fun gogo TDA1557Q_CNV_2.pdf TDA1557Q_CNV_2.pdf
  21. Hello Da years and years on a computer and I never thought of that thanks audioguru gogo just learn something new
  22. Hello It depends on the relay on how much voltage and curent you need I sometimes use electronic relays that can be triggerd by 3 volts, not sure how many Mamp's but the Pic supplies enough and the relay can handle 220V at 20amps. A driving transistor works and some will say opto's will do the job too. I guess it all depends on what parts you plan on using. have fun gogo
  23. Hello I use Egale freeware. diptrace looks to be the same except it cost a lot more have fun gogo
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