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  1. hevans1944

    Looking for a consumer integrated circuit...

    Try this Yahoo! link. Other search engines, such as Google, may provide more or different results.
  2. hevans1944

    making a big magnetic field

    As was noted in a 1983 movie (Matthew Broderick in WarGames), vis a vis thermonuclear war: The best way to win is not to play.
  3. hevans1944

    help me to design 60w portable power supply

    Well, the problem is we only provide help with homework problems... not completed designs. And, as @davenn noted, you didn't answer his or my questions. If all you are looking for is a "canned" solution that you can submit in class as your own work, so surf the web. There are plenty of designs...
  4. hevans1944

    help me to design 60w portable power supply

    @ALJOHANI22 You specify "Input: 12 Vdc" and "have an internal rechargeable battery for when a mains connection isn't available." Last time I looked, mains connection in the UK is about 240 VAC. So which is it? Mains power or battery power or both? Also, you stated "Must be able to maintain the...
  5. hevans1944

    International Rectifier B5CNQ015 (House Number?)

    Could you have misread the part number? Maybe 85CNQ015 instead of B5CNQ015? Can you upload a close-up picture of the device?
  6. hevans1944

    making a big magnetic field

    Creating a destructive EMP typically requires discharging a high voltage capacitor or a high voltage energy-storing delay line into a radiating load (an antenna) using a very fast switch. The faster the turn-on, the more high-frequency content in the radiated EMP. Pulse widths of a few...
  7. hevans1944

    Need help with switch...110v and 12v.

    Most relays come with either Form A or Form C contacts. Form A contacts are a single pair of contacts that are either normally open or normally closed when the relay coil is NOT energized. From your description, you would want a normally open Form A contact. Form C contacts offer BOTH a normally...
  8. hevans1944

    Lens info needed

    @Jouellet The lens system will be greatly affected by several parameters: length of beam "throw", size of beam at the desired distance, shape of the beam, sharpness (or lack thereof) of beam edge, diameter of beam at the source, and diameter or effective area of the LED source. It may be...
  9. hevans1944

    Need help with switch...110v and 12v.

    Make sure the relay coil is rated for 110 VAC (NOT DC!) and the contacts are current- rated for whatever 12 VDC load you want to switch. Wire the relay coil in parallel with the lamp so the relay energizes when the lamp is on. Use normally-open contacts on the relay to switch your 12 VDC power...
  10. hevans1944

    Lens info needed

    A good place to start is Edmund Optics. If you know nothing about optics, they can help bring you up to speed with that too at Scientifics Online.
  11. hevans1944

    IGBT Sine Wave Dimmer

    It's too bad the Chinese to English translation is as poor as it is. Clearly the first circuit is a high-frequency (50 kHz) chopper that is pulse-width modulated. This will provide, after filtering out the harmonics of the 50 kHz switching frequency, a reduced amplitude sinusoidal waveform whose...
  12. hevans1944

    LED strobe controller IC replacement

    Pretty good picture but it confirms my suspicion that the 14-pin chip is probably an application specific integrated circuit (ASIC) and is probably unobtainable. Note there is provision on the circuit board to add two more "882" power transistors (whatever those are!) so there are probably other...
  13. hevans1944

    LED strobe controller IC replacement

    Oops! I didn't know that. They are probably illegal in all states for anyone except LEOs. Oh, no "sir" is necessary. We're all "just folks" here. You can address me by my nickname, Hop.
  14. hevans1944

    LED strobe controller IC replacement

    Well, don't feel alone out there. There is plenty of help available here when you are ready to try building your own strobe controller. Flashing LEDs is one thing though... flashing headlights is more effective, but much harder because of the way incandescent lamps behave electrically (high...
  15. hevans1944

    LED strobe controller IC replacement

    Is this by any chance an automotive application? Hazard warning lights for a tow-truck perhaps?
  16. hevans1944

    Random LED Colour Changer

    I think they do watch closely for cash money being brought into Mexico illegally. And with the porous border going from Mexico to the States, it is apparently not much of problem getting contraband out of Mexico. Heck, with NAFTA, they probably ship in tractor-trailer trucks now.
  17. hevans1944

    LED strobe controller IC replacement

    The picture tells us nothing. Please take a close-up photo of the 14-pin IC showing the factory markings. This may not help much if this is the only IC on the circuit board. There are probably some power transistors too that actually provide current to the LEDs, but a picture of the bottom side...
  18. hevans1944

    Random LED Colour Changer

    There are human factor considerations too. Presumably there will be a "guard" or someone of appropriate authority stationed near the exit to stop and search any employee who happens, by chance, to get a "red light" instead of a "green light". That probably means you want the "red light"...
  19. hevans1944

    TI PCM3070 microprocessor beginner problem

    I would highly recommend that you purchase the PCM3070EVM-K Evaluation Module, about US$200 directly from Texas Instruments. This will provide you with a USB programming interface to a PC and software to get you started. Visit www.ti.com for complete information on what is available. To...
  20. hevans1944

    Looking for TW8823 LCD controller documentation

    Try using Google search engine with this string: Intersil TW8823
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