Search results

  1. audioguru2

    Re-called Light Bulbs

    Hi Rhonn, Wow, you buy compact flourescent bulbs for only a quarter of a $US? That's the price I pay for the old hot short-life incandescent bulbs. The cheapest I've seen are 4 for $10US. I went to buy them but they were sold-out. You could hack the Mosfets and other good stuff inside them...
  2. audioguru2

    Voltage Multiplier

    Hi Clark, Are you serious? You're going to power 42 LEDs (a traffic light?) with a 4" PC's fan? Ha, I figure that to develop nearly 4W of wind resistance (which won't be neglegible) the little fan will need a wind nearly the speed of sound! You'll need to step its voltage down, not up, to get...
  3. audioguru2

    Re-called Light Bulbs

    Hi Guys, A local light bulb importer is re-calling millions of Chinese-made compact-flourescent light bulbs. Apparently, many are failing and although are properly made with fire-extingueshing plastic, they melt all over the place! Ouch if you're under one! Adding to the problem is that the...
  4. audioguru2

    Convert 0-30V 3A PSU to 5A or more

    Hi Dazza, I wouldn't use a supply with adjustable voltage and current controls to charge a battery. A kid comes along and fiddles with it or you accidently bump it and you have a very dangerous situation. The charging characteristics of each battery type is different, although a Ni-Cad and a...
  5. audioguru2

    Voltage Multiplier

    Hi Clark, I still think your motor/dynamo has a DC output. An AC motor usually doesn't have the required permanent magnets to make it a generator. The alternator on a car uses battery power to make magnetism for its field coil. Why multiply the voltage to drive a 2V LED? With a 10V output...
  6. audioguru2

    Infrared Light

    Hi Yevgeni, Questions about your nice parking helper circuit: 1) Doesn't the sensitivity of the circuit depend on the reflectiveness (colour and shinyness) of the wall? Perhaps it should have a sensitivity adjustment. 2) Wouldn't the circuit be more stable by using a lower-voltage regulator? If...
  7. audioguru2

    Convert 0-30V 3A PSU to 5A or more

    Hi Guys, A battery that is charged from a regulated current supply does not become a lighter load. It will continue to draw the same amount of regulated current that you have set for maximum, but after it is fully charged will convert the entire charging power to heat and gasses. If the charging...
  8. audioguru2

    Voltage Multiplier

    If the output cap is too big it will take a long time to fully-charge from the smaller charge that is "dumped" into it from the smaller doubling caps on each half-cycle of the AC. Look at the staircase signal in the posted article. Fill a bucket with another same-size bucket or use a teaspoon to...
  9. audioguru2

    Who is using the oldest computer?

    Hi Ante, I've sneaked into my son's Pentium4 many times when he's at work. I don't do any rocket science or heavy number crunching so there isn't much difference. His computer opens a PDF file immediately, mine takes a couple of seconds. With both on high-speed cable internet, his access to a...
  10. audioguru2

    Who is using the oldest computer?

    Hi Ante, Yeah, good computers are cheap now, but I am a thrifty tightwad. :-[ I'll probably get my son's Pentium4 when he gets a better one soon. In the meantime, my 486 still rocks! ;D
  11. audioguru2

    Voltage Multiplier

    Hi Clark, A voltage multiplier will not give more power output than the dynamo already gives. It increases the voltage output by rectifying AC and adding the capacitors' voltages, and its output current is reduced by the same mulipication amount. Just like in an AC transformer, power (voltage...
  12. audioguru2

    Who is using the oldest computer?

    Yahoo! Yahoo! Yahoo! Yahoo! The IE5 browser that I installed on my 486 computer allowed me to enter Microsoft's site. There I analysed and downloaded IE6. I installed it and it works great! A bit slow...
  13. audioguru2

    Convert 0-30V 3A PSU to 5A or more

    Hi Kain, Good, you'll have a nice and small, cool PCB. ;D Are you going to use an aluminum-cased and small-finned resistor with a 25W rating?
  14. audioguru2

    Convert 0-30V 3A PSU to 5A or more

    Hi Kain, Your PCB is going to be really small. Allowing space for mounting bolts and a 15W resistor for R7, where are the rest of the parts going to go? ;D
  15. audioguru2

    Power Supply and battery life

    Hi Ryan, Nobody seems to make a 74HC4026 which is a low-voltage version of the IC in our counter project. Since you are a Newbee, why not make our project as it is. If it needs more voltage than your coin cell, you could add an 8-pin and 2 capacitor ICL7660 or MAX1044 voltage doubler IC, or just...
  16. audioguru2

    3V LED Chaser project

    Hi Guys, You know what a traffic accident scene looks like on a highway at night? That's what my place looks like with my 3V LED Chaser projects flashing all around! I was thinking about using the very expensive Lithium AA battery cells that I got as free samples for longer battery life, but...
  17. audioguru2

    Power Supply and battery life

    Hi Ryan, Welcome to our forum. To calculate battery life you need to know how much current that a circuit is drawing. That counter project uses ordinary Cmos ICs that draw nearly zero current. But its LED display draws a huge current. You must figure how long the display will be lighted. A good...
  18. audioguru2

    Who is using the oldest computer?

    Hi Ante, The original clock/bios soldered-in battery on my 10 years old 486 computer still works so it and I can wait until Intel replaces the Pentium with something better. Then my son will give me his Pentium 4 or one of the many computers that he gets cheap on E-Bay then sells for a good...
  19. audioguru2

    Car stereo amplifier output ratings

    Hi Matthew, There is no such thing as a "musical watt". Music varies considerably in volume, frequency and time duration at maximum level. Frequently there are moments in music where many instruments' output phases are all "in-phase" creating a massive output level. Do you want the amp to clip...
  20. audioguru2

    Problems with headphones... static?

    Hi Acker, It's too bad that magnetic radiation isn't the cause of your noise problem. It could be that your computer performs normally, which isn't good enough for you being a perfectionist. There is a lot of digital crap flying around inside a computer which is difficult to keep from corrupting...
Top