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  1. hevans1944

    Voltage Doubler problem

    Correcto! However, a mains-operated voltage doubler will allow incredibly fast xenon flashing rates, especially if the follow-on circuit has inductor/SCR energy management of the xenon tube discharge. It depends on the minimum cycle time requirement, which was not specified. I once built a...
  2. hevans1944

    Convert a 6 volt to 12 volt on my motor cycle . Any ideas how that's done

    You can ask anything here. I found a wiring diagram for your motorcycle. Does it make any sense to you? If not, then changing from a 6V system to a 12V system is not your cup of tea.
  3. hevans1944

    Convert a 6 volt to 12 volt on my motor cycle . Any ideas how that's done

    It is easy to up-convert a 6 V system to 12 V to operate modern accessories: just add a boost converter that powers only the added components. Is there a problem obtaining a 6 V motorcycle battery? Is the alternator on the fritz? Please tell us: WHY do you want to go the expense and labor of...
  4. hevans1944

    555 PWM 0%?

    Whut!? I thought Chinese eBay shipped world-wide.:D
  5. hevans1944

    Power for 200 flashes

    Are you sure the power supply you cited is compatible with the flash unit you cited? The flash unit will accept an external power supply to replace the internal batteries, but this would be a low-voltage power supply providing the same voltage as the four AA-size internal batteries: 6 V DC...
  6. hevans1944

    Inductive sensor interference

    Since inductive proximity sensors depend on a magnetic field for their operation, it will be difficult to "shield" one from the other even if they are mounted at right angles to each other. Please upload a photograph showing how these sensors are mounted and provide us with information as to...
  7. hevans1944

    555 PWM 0%?

    You cannot get zero percent duty cycle from any kind of oscillator, else it wouldn't be oscillating! You need a more sophisticated circuit to obtain zero duty cycle. Google PWM circuits. Some of these do allow 0 to 100% duty cycle adjustment. Or try "loading" the LED with a parallel resistor to...
  8. hevans1944

    120VAC to 12VDC Power Quality Problem? HELP!

    I suspect you mainly want to run your LED strip lighting off the marine battery when parked out there enjoying the wilderness, hopefully without running a motor-generator set into the wee morning hours, but would also like to run from "shore power" when the camper is connected to a 120 VAC RV...
  9. hevans1944

    120VAC to 12VDC Power Quality Problem? HELP!

    It is important to measure the LED current when they are powered on with a stable DC source, like your marine battery. Some switch-mode power supplies will shut down if they "think" they are being overloaded, although a 120 VAC to 12 VDC converter properly protected with 15 A line fuses is...
  10. hevans1944

    Voltage Doubler problem

    Yeah, most common is installing the electrolytic capacitors with their polarity reversed. That will do it every time and may cause the capacitors to explode if current-limiting resistor doesn't burn out first, acting somewhat as a fuse. Please don't power this circuit directly from the AC mains.
  11. hevans1944

    Stepper motor driver blown switching power transistor

    Is this a commercial product you are "working on" or your own design and construction? That fuse is blowing for a reason. Upload more information or quit wasting our time. And welcome to Electronics Point!
  12. hevans1944

    How to build Circuit

    And you should also make sure that the 24 VDC power source can provide enough current to operate the SMPS that delivers 8 VDC at 8 A. That is 64 watts of output power, so input power capability needs to be about 70 watts (assuming about 90% SMPS efficiency) or about 3 A capability from 24 VDC...
  13. hevans1944

    120VAC to 12VDC Power Quality Problem? HELP!

    Welcome to Electronics Point! Have you compared the current drawn by the LED strip lighting against the current rating of the 120 VAC to 12 VDC converter? It's possible the latter device is automagically shutting down when the LED load is added. Easy solution is to add a largeish electrolytic...
  14. hevans1944

    Voltage Doubler problem

    This is a standard half-wave voltage doubler circuit. The diodes and capacitors are drawn correctly. The purpose of the resistor is to limit the charging current of the two capacitors. Each diode conducts alternately on the positive and then the negative half-cycles of the power line, charging...
  15. hevans1944

    Playing with transformers and resistors....

    Welcome to Electronics Point! Would you please visit this Google page and tell us which "six pin device and no markings" device you would like to use? If possible, take a picture of it and upload the picture here. Maybe someone can help identify it. It might be a dual potentiometer if it has...
  16. hevans1944

    Heat sinking compounds

    No it is NOT true. Ideally, heat-sink compound would not absorb any heat. Instead it would allow whatever heat is generated by the active device to pass freely through the thin layer of heat-sink compound into the attached heat sink, whereupon the heat is transferred to the environment. In...
  17. hevans1944

    Thermostat with lm35: help finding out the error

    Expanding on Steve's comment in post #5: The LM393 has an open-collector output that will sink (typically) 16 mA when the output is "low" and will present an open-circuit when the output is "high". To drive the relay coil, you connect one side of the coil to +V and the other side to the LM393...
  18. hevans1944

    Optical Encoder Issue

    It is an Agilent HP 9730 with two quadrature-spaced detectors and a single LED illumination with integrated lens. This is to be used with a "bar and window" strip of appropriate cycles per unit length to create quadrature outputs on two channels. It is also suitable for use with a rotary encoder...
  19. hevans1944

    How to find Area of Hysteresis?

    For non-analytical areas like the one shown above, print the curve on heavy paper and carefully cut the outline out. Weigh the cut-out with an analytical balance. Compare the weight against a square or rectangular cut-out of known area. The areas will be proportional to the weights you measure...
  20. hevans1944

    Location devices

    Well, as you noted, it doesn't work with ultrasonics if there is anything in between. Problem doing it with RF is timing constraints. So, yeah, let's hear from the OP about what he is trying to DO before providing anymore "advice" on how-to-do-it.
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