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  1. hevans1944

    novelty led blinker, how is it done?

    See what you can do to extend battery life by limiting the on time (short duty cycle) and the forward LED current? Having two AA cells helped a lot, but that's not cheating. The OP needs to learn about project power requirements and energy capacities of various storage devices before stepping...
  2. hevans1944

    novelty led blinker, how is it done?

    That's why you need a PIC microcontroller... the LEDs are only briefly "flashed" to minimize their energy consumption. A few years ago at a Dayton Hamvention an antenna tower vendor was giving away stickers with a red LED mounted at the top of the image of a tower printed on the sticker. The LED...
  3. hevans1944

    novelty led blinker, how is it done?

    You need to visit this website and learn about PIR motion sensors. Then add a small microprocessor, such as a PIC made and sold by Microchip, with a program you write that creates pseudo-random activation of your shamrock LEDs after motion is detected by the PIR sensor. Easy peasy. You should be...
  4. hevans1944

    Increasing Battery life Question

    Ha! I thought everyone knew that Chinese carbon-zinc D-size cells consisted (at most) of a single AAA cell packed tightly into sand to bring the weight in line with other commercial D-size cells. You be real rucky to get a hunred milleramps for ten minits from one of them puppies.
  5. hevans1944

    Increasing Battery life Question

    Looks like this was yet another drive-by poster looking for a quick answer. Not finding it, they moved on. They left one (and only one) post on December 4, 2018 and joined EP the same day. No further activity. IMO, a moderator should probably close this thread to further replies, at least until...
  6. hevans1944

    Increasing Battery life Question

    I think I would revisit the design of the little machine that fires tennis balls for your dog. Why is it powered with D-size dry cells, and how much current does it draw throughout the firing cycle? Is this a commercially available contraption, or something you cobbled together from, say, used...
  7. hevans1944

    Connecting 2 micro controlers at high speed

    You might want to visit this page and read the comments therein. Or maybe forego the UART approach entirely and bang on the GPIO bits with some well-crafted assembly code. Some help with that might be available here. An asynchronous data transfer protocol, which is what a UART implements...
  8. hevans1944

    Figured I'd say hi

    Welcome to Electronics Point, @Faraday's Cage! Where are you from and what are your interests?
  9. hevans1944

    Monitor the AC and DC current analysis through Thingspeak

    Go to this link to get started.
  10. hevans1944

    Need a simple adjustable device to lower signal voltage?

    @Alec_t: I bought an unheated Bosch O2 sensor years ago, thinking I could heat it to operating temperature with a Mapp gas blow-torch and learn a little more about how they work. Back in the day, my then employer, UDRI, was working on O2/CO2 sensors for a sponsored research project involving...
  11. hevans1944

    Need a simple adjustable device to lower signal voltage?

    Okay, so now we are getting somewhere and we know what you want to do. I know diddly about modifying or tuning motorcycle engines, but it seems that most "improvements" fall into one or both of these categories: improve the aspiration of the fuel-air mixture during the intake cycle or improve...
  12. hevans1944

    When we usding lm IC

    Download the datasheets (use Google to find them), read them, make a decision based on which features you need or want.
  13. hevans1944

    Need a simple adjustable device to lower signal voltage?

    So, what's wrong with the original oxygen sensor signal going into the engine computer? Why do you want to mess with this signal? You cannot change the oxygen sensor voltage without also changing the oxygen sensor current. Why are you trying to do this? Please tell us WTF you are trying to DO...
  14. hevans1944

    Question about ACS758 current sensor

    The biggest problem IMHO in using the Allegro chip is the analog output is offset to half the supply voltage when there is zero current present. So, for a typical 5 VDC supply, the output swings from about +2.5 VDC to 0 VDC for increasingly negative currents and from about +2.5 VDC to +5 VDC for...
  15. hevans1944

    Question about ACS758 current sensor

    That is absolutely NOT TRUE. With the availability of free application development software and really cheap microprocessors, the only limitation to creativity is your imagination. Back in the 1970s, when microprocessors were just becoming available, it required a small fortune to breadboard...
  16. hevans1944

    Question about ACS758 current sensor

    I like this idea, especially if there is no telemetry involved, just a pre-flight check on the ground. Unfortunately OP lives in Canada and the vendor at the link shown does not ship to Canada. OTOH, here is a link for what is probably the same Asian product that will ship to Canada for $US...
  17. hevans1944

    Types of LED bulbs inside circuitry ?

    Yes, you are right. And most of us (me included) do appreciate your sense of humor here on EP.
  18. hevans1944

    Help with timers

    No, not "oops!" We now have a fresh thread in which to discuss automatic dog washes (or sheep dips), hopefully with some relevance to helping someone with timers... perhaps even electrical or electronic timers, with perhaps a side bar on instant water heaters with pro and con discussions of how...
  19. hevans1944

    Types of LED bulbs inside circuitry ?

    NOT. Helmets were a marketing ploy having almost nothing to do with personal safety. Compare the modern users of bicycle helmets, motorcycle helmets, football helmets, combat war-helmets, baseball batting helmets, deep-sea diver helmets, jet fighter pilot helmets, astronaut helmets, and coconut...
  20. hevans1944

    Help with timers

    This thread was almost five years old before @Petkan "bumped" it to the top of the list. KrisBlueNZ passed the year after the thread was started. The original poster (OP) hasn't been seen since June 8, 2014, three days after their original post. So I guess we have now hijacked this thread...
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