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  1. J

    Xbox360 psu's to power car amp

    so what are you looking for 24V output or 12V output twice the amps? When wiring in series you will need to cut one of the grounds or this will surely short one of the PSU's out.
  2. J

    LCD tv power/inverter board

    What is that black stuff on the bottom of the second board with the missing chip? Is this the second board you where talking about? edit: guess i should read before posting, you already explained which board was what.
  3. J

    Removed anode from my SCR

    Why would they cut off the anode pin on a SCR? Would make sense if the tab was electrically connected to the anode, but I looked at the datasheet and I didn't see where it stated this. http://cs.utsource.net/goods_files/pdf/22/22042_STMICROELECTRONICS_BTW69N1200.pdf edit: well the MM reassures...
  4. J

    LCD tv power/inverter board

    Check the bridge rectifier. We are still talking about the second one that doesn't work at all right?
  5. J

    how can i fix a radioshack 29 range multimeter?

    Opening them up would be a start. Check for blown components and other odd looking signs of burn marks.
  6. J

    12V/DC - Duracell battery bank?

    Make sure you know your battery. Each type has specific charging and discharging requirements to maximize life. Battery university has a lot of information. I suggest you at the very least, take a look.
  7. J

    Tying into a pinball light matrix

    Start here and post a schematic. It is rather hard to visualize something you never seen.
  8. J

    LED Circuit Design Help

    I think they are removed for spambot reasons, but any member can always PM you their e-mail address or vice versa. No, biggie, i just found it comical. Hope someone can help you out.
  9. J

    Diode resistance

    First google hit. Sucky video, doesn't help. But google returned a few pages of results. Surely you can search through them Here is a better page http://www.learnabout-electronics.org/transistor_faults_04.php
  10. J

    Diode resistance

    Depends on the type of transistor you're testing. Google will surely help you in this matter
  11. J

    Diode resistance

    Well a diodes resistance will change with temperature as well. So the best way to know the resistance is to take the Vfd and divide it by the current. Ohms law!
  12. J

    Diode resistance

    A diodes resistance is not linear. As a forward biased diode has very little resistance as opposed to a diode that is reversed bias(within max limits of the device), as long as you are talking about normal diodes. Things change when you start talking about other types of diodes.
  13. J

    LED Circuit Design Help

    Well if nothing else I applaud your attempt at bypassing the site rules on e-mail addresses. ;)
  14. J

    Re-winding a 24v solenoid to 12v

    Not knowing a whole lot myself, I would assume that inductance will have a say since it is a coil of wire. I know it doesn't help you out. Hopefully someone else will be able to clarify what needs to happen. I will be reading with interest as well.
  15. J

    music.

    and that smart-y is not usb, it is ps2 which is as old as dirt.
  16. J

    music.

    http://www.google.com/products/catalog?hl=en&gs_nf=1&tok=ILlV7T7POl0UvemIOewopg&cp=10&gs_id=12&xhr=t&q=serial+to+usb&gs_upl=&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&biw=1680&bih=925&um=1&ie=UTF-8&tbm=shop&cid=6453028244276719865&sa=X&ei=HtxLT6Fsh6zQAfrr3akO&sqi=2&ved=0CJYBEPMCMAM
  17. J

    transistor pain

    seeing as how you have two different voltages, I would use an NPN. That way you have a common voltage to turn the transistor off. to select the base resistor is quite easy. We know the max C-E current of the 2N3904 is 200mA and if the gain of the transistor is 100 min. then 200mA /100 = 2mA...
  18. J

    transistor pain

    I believe so. The 3906 is only rated at a max 200mA continuous collector current. You also need to remember that the transistor has a voltage drop across it as well, so the voltage the motor sees is less then 9V. So either you have to low voltage or not enough current to drive the motor. It...
  19. J

    transistor pain

    Let me start again. A PNP transistor turns on when the base is more negative in respect to the emitter by about -0.7V. You have 9V on the emitter and 0 - 5V on the base at any given time. This should keep the transistor in the ON state continuously. What is the current rating of the motor?
  20. J

    transistor pain

    Sry, disregard what I said earlier, it was totally wrong.
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