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  1. Hero999

    HI

    Sounds good, please post the schematic and source code.
  2. Hero999

    timer to trigger latch

    I don't know, you drew the circuit. They look like SCRs to me. Seriously, use a microcontroller, the PIC12F508 could easilly do what you want or better still save up or take a bank load to buy the propper welding mask.
  3. Hero999

    how to build a quality inverter

    You could use a boost converter to get +35V and a buck boost to get -35V but it's probably more efficient to use a transformer based topology i.e. flyback or forward converter.
  4. Hero999

    data transmmition with laser pointer

    Have you Googled? As it only neds to transmit over 1m why not drop the laser idea and use a standard IR LED and remote control receiver IC?
  5. Hero999

    power electronic

    It's easy, use phase control. http://en.wikipedia.org/wiki/Phase_control To adjust the brightness, alter the delay of firing of the thyristor, the later the firing, the dimmer it will be.
  6. Hero999

    how to build a quality inverter

    Then you need a DC-DC converter, not an inverter. You could wire six 12V batteries in series to give you +/-36V or you could use a pridge amplifier to give the same output power from a single 36V power supply.
  7. Hero999

    DC Potentiometer in AC circuit to control DC output.

    The resistor in series with the LED is 1k and the load is 1k, giving a total load impedance of 500R, ignoring the LED's forward voltage drop. The output voltage can be calculated using the potential divider formula which can be found on Wikipedia. http://en.wikipedia.org/wiki/Potential_divider
  8. Hero999

    DC Potentiometer in AC circuit to control DC output.

    Please post a schematic. You can't use a potentiometer to vary the voltage to a large load because the output impedance of the potentiometer is too high so the output voltage will drop. Furthermore, the potentiometer is probably only rated to something like 0.25W and will burn out if the...
  9. Hero999

    design with DAC0808

    No because it's not the right IC to use for that application.
  10. Hero999

    toner transfer from Orcad PCB Design

    I've never used OrCAD before but on most PCB packages you can turn off layers you don't need and print the board for toner transfer.
  11. Hero999

    toner transfer from Orcad PCB Design

    I'm not sure what you're asking. Just open the file and print the copper layer. Turn the silk screen and solder resist layers off.
  12. Hero999

    how to build a quality inverter

    Buy an inverter and add a transformer to the output. If you can't get a 45VAC transformer then connect a 30V and 15V transformer in series.
  13. Hero999

    Project Help (making a clock from 4 switches)

    The lamp won't light with a 1k resistor connected in sereis with it.
  14. Hero999

    Need Help for this simple Relay Driver Circuit

    The original poster has opted for a 230VAC relay,  he's has the sense to realise using a DC PSU to power a DC relay was a silly idea. Using an LM7806 to power a relay, are you crazy? Totally silly idea. In developed countries the mains is regulated to within +/-10% of the specified voltage and...
  15. Hero999

    Logic Level Mosfets

    You're wrong about how MOSFETs work. They have other modes of operation than just on and off. The gate voltage just needs to be high enough to allow enough current to flow through the load and a small voltage drop across the MOSFET. The maximum gate voltage depends on the device and normally...
  16. Hero999

    120V shorted out, why did the lights get brighter?

    Yes the lights should get dimmer when more current is drawn..I don't know, perhaps the tap changer inside the transformer supplying your house switched to a higher voltage tap to compensate for the voltage drop created by the surge.
  17. Hero999

    How to hook up a transformer

    No you can't skimp on the switching feature which is required for the transformer to work. The switching regulator converts the DC to high frequency AC (30kHz to 300kHz) to power the transformer which will not work on low mains frequencies (50 to 60Hz). If you connect the transformer directly to...
  18. Hero999

    Turning on +12V bulb with slow ramp opto device

    Good decision, many people are scared of MCUs for some reason. It's possible to do this with a couple of 555 timers or some comparators but it won't be anywhere near as simple as with a MCU. The problem is the long 10 minute delay which isn't easy with a 555 timer because the RC values need to...
  19. Hero999

    Turning on +12V bulb with slow ramp opto device

    Why torture yourself? Use a  simple microcontroller such as the PIC12F508 or one which has a built-in PWM module such as the PIC12F683, if you want simpler code.
  20. Hero999

    Need Solution for this Simple Stupid Question

    This has got to be one of the funniest threads ever. :D
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