Search results

  1. audioguru2

    portable DVD battery pack

    The DVD player uses 3.5A? That is an awful lot of current to supply from a battery for 8 hours. I've never seen rechargable battery cells with such a high capacity as in the last post but you would need about 24 of them. They will cost an arm and a leg. :(
  2. audioguru2

    How Microwave Oven Work?

    Everything that people don't understand works with majic. www.howstuffworks.com explains pretty well about majical things. ;D
  3. audioguru2

    BJT power supply

    Hi Guys, If Alun uses a P-channel Mosfet in his circuit then he won't need a 555 voltage doubler. ;D The MC33171 is a low-power fairly slow opamp. I would use a faster one.
  4. audioguru2

    DC Motor Booster

    By boosting the drive power to the motor, it will be overloaded. Then the door opening quicker will help blow away the smoke! ;D ;D
  5. audioguru2

    0-30 Vdc Stabilized Power Supply

    Hi Spagbol, Welcome to our forum. ;D You have an excellent idea to use gain in the supply circuit's output stage to reduce the high supply voltage requirement for the driver opamp. I have seen high power audio amps with very high supply voltages, gain in the output stages and opamp drivers. I...
  6. audioguru2

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

    Hi Narog, Your positive current sensor opamp has positive feedback and therefore won't work. :( Your negative current sensor opamp circuit is correct. ;D The 1k resistors in the current sensor circuits will get mighty hot. Use 10k. The 0.47 ohm current sensor resistors will also get mighty hot...
  7. audioguru2

    Coil gun charger circuit

    Hi Steven, I can't remember the supply voltage for your LED, its 1k current limiting resistor and 2N3904, but a simple calculation will show how much power the resistor must dissipate. If your supply is 24V, then the 1k resistor will dissipate about 484mW. ;D
  8. audioguru2

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

    Hi Again, I think your output transistors will also quickly melt if your circuits supply 5A at a low voltage. :'(
  9. audioguru2

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

    Hi Narog, Welcome to our forum. ;D I don't have Electronic Workbench so I didn't see your zipped file. I like the way you added an opamp then sensed the current in the active supply, instead of sensing the ground current in our project. ;D But the opamps sensing both supply's currents have...
  10. audioguru2

    supplying power to 12v 1.4a, 3v 3a with a diy power supply

    Hi Chylid, You used 50Hz in the formula for the filter capacitor. The full wave bridge rectifier doubles the frequency, so a capacitor half the value of the one you calculated will be fine. The rectifier diodes conduct only when the voltage of the rectifier exceeds the capacitor's voltage, for...
  11. audioguru2

    Sequential Timers with PWM Motor Speed Control

    Hi Guys, The video wasn't in my Temp Internet Files because my cache setting was too small and was full. After viewing the video online again I found it and zipped it. Twice I tried to post its 9.4MB zip file but it didn't appear here. I've been having trouble with Electronics-Lab pages not...
  12. audioguru2

    Sequential Timers with PWM Motor Speed Control

    Hi again, While the "800" size video was playing I looked at the processes that were running. It showed an IE6 process adding up to 35MB. I can't find where it is stored on my PC and even if I zip it it might be too big to post here. How long would it take a dialup connection to download 10MB? ???
  13. audioguru2

    Sequential Timers with PWM Motor Speed Control

    Hi Ante, I searched for a HydroFoam, the video's number and part of it as shown in its properties, and every video on my computer with a size greater than 1MB. I found your flying Lawnmover and even a Citroen 2CV blowing-up. I'll play the video again (hoping that it doesn't just get it from the...
  14. audioguru2

    Sequential Timers with PWM Motor Speed Control

    Hi Ante, I went to Nokia's website and searched for Bluetooth. They have a long list of phones that have it but not mine! My internet cache has never been cleaned and is jam-pack full of all kinds of things, including all the viruses and junk found by Norton and my anti-adware which is...
  15. audioguru2

    LM317 Variable power supply

    Yeah, the cheap little 1N400x rectifier diode is too small for much current. :'(
  16. audioguru2

    Sequential Timers with PWM Motor Speed Control

    Hi Alun, I think the "boats" video is "streaming" and you can't download it, so I think you need a high-speed internet connection to see it. :'( I was going to ask how but found this in their forum: Q - How do you download music and videos that are hosted on Putfile.com? A - you dont My son...
  17. audioguru2

    Sequential Timers with PWM Motor Speed Control

    ;D ;DHa, ha, he, he, ha, ha. A lawnmower that flies, does loops amd smokes like my old lawnmower. Now I've seen everything! ;D ;D Thanks.
  18. audioguru2

    Sequential Timers with PWM Motor Speed Control

    No I didn't see it. Does it also fly?
  19. audioguru2

    BENCH POWER SUPPLY

    Hi Um...Me, My LM317 power supply uses a little heatsink like yours, supplies up to 1A from 1.25V to 9V perfectly, gets pretty hot but doesn't shut-down, and is powered by a 12VDC/1A wall-wart adapter. Maybe you should use a 20V center-tapped transformer (10V-0V-10V). You can switch the...
  20. audioguru2

    Opinion on a brand of solder wire

    It looks like it is perfect for handsoldering, is very good and is high quality. Pleasant pine smell? I'm going to get some. I bet it is expensive, but who cares if it is better. Wait a minute! Its rosin is water (aquious?) soluble. Then it might conduct in high humidity. It would ruin my...
Top