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  1. hevans1944

    Running incandescent or halogen bulb with 2/3 or lower voltage possible?

    I have an overhead lamp fixture in my kitchen/dining area consisting of five incandescent lamps all connected to a nearby wall dimmer. At night we turn the dimmer down to minimum so as to provide a "night light" in the kitchen. Originally, this was fitted with five 40 watt, clear glass...
  2. hevans1944

    Soldering Wires

    Unless the motion sensor is built-in to the camera, and is designed to take a picture when the sensor is "triggered," you need a remote shutter release. What other reason would you have to hack your cameras? Unfortunately, the advice I gave you is not applicable to the cameras you have: they...
  3. hevans1944

    Soldering Wires

    You need to get a camera with a remote shutter actuation feature. The remote actuator is a flexible but stiff wire in a protective sheath that screws into the shutter release button. On the other end is a thumb-operated plunger that pushes on the wire to actuate the shutter, but you can also...
  4. hevans1944

    Can you stack/parallel an LM1117-3.3

    The TI Application Report is for a different LDO regulator, and it says their circuit is not recommended for output voltages less than nine volts because of inadequate transient response and stability problems, whatever that means. Your Mileage May Differ. However, I am sure there are similar...
  5. hevans1944

    Cleaning a PCB

    You should always be careful to avoid static discharge when working with circuit boards that have static-sensitive components, such as CMOS, installed. That generally means a conductive anti-static mat connected to an earth ground (green-wire ground in the U.S.A.) to place your circuit board on...
  6. hevans1944

    Cleaning a PCB

    Wow! Thanks, Adam. They sell these here in the States through Amazon too. Just need to find the right Google search string, which your link provided.
  7. hevans1944

    Cleaning a PCB

    I generally prefer plain old isopropyl alcohol, anhydrous if I can get it, but 91% is commonly available at drugstores such as Walgreen's. Don't use "rubbing" alcohol as it contains too much water. The alcohol is usually much cheaper than commercial "contact cleaning" products and leaves no...
  8. hevans1944

    LM13700 Amplifier/VCO Circuit

    The link to your original thread is here. I or someone else will get back with you after reviewing the original thread. The LM3700 takes some getting used to. It is a variable-gain transconductance amplifier. Very versatile, but you need to think "outside the box" to use it effectively. Please...
  9. hevans1944

    Can I connect a Car Lighter Adapter directly to a car battery and use it to power electronics?

    That adaptor is designed to plug into the cigarette lighter receptacle in place of your missing lighter. Make sure if you plug something electronic into that original lighter receptacle that it works. If not, there is probably a fuse blown. I am astonished that if you plug a fan into the...
  10. hevans1944

    AC and DC Voltages for Electrolysis

    Low currents MAY be better if they prevent a layer of gas bubbles from forming on the anode and cathode. Those bubbles don't conduct electricity as well as the electrolyte does. This is just my guess because it has been years since I played with electricity and conductive water solutions. And...
  11. hevans1944

    Op-Amp Circuit Help

    Because of the negative feedback through R3 and the high open-loop gain of IC1, the potential at the - input is the same as the potential at the + input. There is zero differential voltage between the - input and the + input: they are "virtually" connected together. That means there is a current...
  12. hevans1944

    HUH?????

    Are you sayin' I am becoming a crotchety old man?:D Mebbe so, because I failed to notice where you posted! Humor is good and Technobable is right up there with psychobable on my list of favorites. I actually enjoyed his pathetic attempt to "prove" his concept on paper using Gauss' Law and...
  13. hevans1944

    Ideas for simple pulse circuit?

    And dirt cheap, too! Zillions have been made and sold. Also available in low-power CMOS configuration for battery-operated equipment.
  14. hevans1944

    HUH?????

    @CDRIVE thank you for not posting any more COS like this.:mad:
  15. hevans1944

    What makes a good high current micro-usb cable?

    We like that here at Electronics Point!
  16. hevans1944

    AC and DC Voltages for Electrolysis

    I've never tried this, but it sounds fascinating. You probably need an electrolyte, but I have no idea what would work. Also, it would be a good idea to connect the primary of the transformer to a Variac (variable AC autotransformer) so you can control the current. Definitely do as @poor mystic...
  17. hevans1944

    would it be possible to run this circuit with a single 9V supply?

    You could "synthesize" a ground from a single nine-volt supply provided it is a "floating" battery supply. OTOH, if your nine-volt supply is referenced to audio common that won't work. Better to add a charge-pump inverter circuit to provide a negative rail from a positive nine-volt supply...
  18. hevans1944

    Ideas for simple pulse circuit?

    This sounds ideal for the ubiquitous 555 timer integrated circuit. Lots of circuits available on the Internet.
  19. hevans1944

    timed relay adjustmemt

    Thanks for being so explicit in what you want the relay to do. And earlier you mentioned that a pair of 10 A contacts will be sufficient. So the only question is whether the solenoid operates on AC or DC and what voltage it requires. I found several solid-state relays (SSRs) that will switch...
  20. hevans1944

    timed relay adjustmemt

    Indeed there is a huge difference between zero and 0.3 seconds... in fact the difference is 0.3 seconds, roughly about the time it takes for the average electromagnetically actuated armature to transfer the contacts attached to it from "open" to "closed" or vice-versa. There are much faster...
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