Search results

Search Forums New Posts
  1. CDRIVE

    How to control the speed of a 24vdc pump from circulating water temperature?

    Stu, Winter is just a few months away for me too. It's a bummer but I may have to wear a shirt on some of those days! :) Chris
  2. CDRIVE

    Help amplifying a tiny current

    The SSR would be wired like this. I X'd out the 10KΩ because I don't see its purpose but replacing the button with AA cells changes the ballgame significantly with much more available power. So if you want to leave it connected it will add only 450uA of current draw when 'DO' goes low. Chris
  3. CDRIVE

    Help amplifying a tiny current

    Heck yeah. They're a MUCH better choice for projects that demand juice. I only suggested stacking buttons because I thought you were committed to them. Chris
  4. CDRIVE

    50Hz sine wave

    Nice chip but the OP wants to generate one of those 'Sino - Soida - Lee' thingies. :) Chris
  5. CDRIVE

    LM4871 amplifier circuit not working, please help!

    Ed, we doubled. Chris
  6. CDRIVE

    LM4871 amplifier circuit not working, please help!

    As per the LM4871 datasheet bringing the shutdown pin to Vdd puts it in Shutdown mode. The amplifier is active when the shutdown pin is grounded. Are you sure you need R3 (4.7KΩ)? I don't see why you can't connect the shutdown pin directly to the uC. Chris
  7. CDRIVE

    Help amplifying a tiny current

    In case you missed his post, Steve posted a SSR that fits your limitations. https://www.electronicspoint.com/threads/help-amplifying-a-tiny-current.280353/page-2#post-1705620 The one caveat is that it's never a good idea to design anything operating at its lower or upper limits. Your desire to...
  8. CDRIVE

    ltspice

    Steven, my first version of Tina was 'Tina-TI' which I downloaded free from the Texas Instruments website. That was many years ago and have been using Tina 'Classic' (not free) since then. I find I can build a schematic in 1/10th the time it takes me in LT Spice but that could be because I'm so...
  9. CDRIVE

    Auto reversing polarity after a few milliseconds (for solenoid control)

    Sorry for persisting in this but we're a tech forum and we don't like leaving mysteries unsolved. I found a U.S. seller on Ebay that list your solenoid valve. His description of operation is exactly like all I've read, including yours. I messaged him to ask why reversing the polarity is not...
  10. CDRIVE

    Auto reversing polarity after a few milliseconds (for solenoid control)

    I googled your valve's PN and got quite a few hits. Unfortunately the ones I read describe its operation identical to the link you provided; Pulse Open - Pulse Close. http://www.plumbingsuppliesexpress.com/item/5933559/ Since your empirical tests prove otherwise just sit tight and wait for...
  11. CDRIVE

    Designing a Time Delayed Relay

    Ha, you just brought back a memory. It was a lifetime ago but yes, me too! I used my old Lionel power pack for AC experiments and my HO gauge for DC. Regarding flux: I never had any issues with paste flux but when I used a clear liquid flux for a uC project that included some Hi Z inputs I...
  12. CDRIVE

    electromagnetism

    Damn, I hate when I do that! He did answer the question but even after going back to post 1 I still missed it. More embarrassing than missing it was the fact that meedo posted it as a reply to ME! :rolleyes: Sometimes I look in the mirror and say.. "What are you looking at Dummy"? Chris
  13. CDRIVE

    Need help with muscle stimulator project

    I don't think your instructor, school, test subject or the school's 'Risk Management' department is going to like your project. Chris
  14. CDRIVE

    Auto reversing polarity after a few milliseconds (for solenoid control)

    Yeah, I read those specs too and there's absolutely nothing in the description that so much as hints that reverse polarity is required or is even relevant for its operation. In fact the description indicates a typical "Pulse On - Pulse Off" logic. Unfortunately the specs fail to specify the...
  15. CDRIVE

    electromagnetism

    Hop, let's get real here. You know that's a totally unrealistic request. EP stats indicate that imperative information isn't divulged until we've veered off into countless dead ends or a thread receives archive status. :D Chris
  16. CDRIVE

    Help amplifying a tiny current

    Well much has been posted since my last contribution when I asked "What is the load that you're switching"? Unless I missed it we still don't know. This would seem rather important. This way we can determine if resistors should be left bare or fully clothed! :p Chris
  17. CDRIVE

    Help amplifying a tiny current

    The link to your relay indicates that it's a 3V coil @ 20 to 25Ω. As Alec stated "Current hungry" because that computes to 120 to 150mA! Chris
  18. CDRIVE

    Help amplifying a tiny current

    Expanding on Alec's last post it has occurred to me that you haven't told us what the load is you're trying to switch on. Care to elaborate? Chris
  19. CDRIVE

    Help amplifying a tiny current

    Here's a schematic of what I described in my last post. I do have a question that i don't think anyone asked you. What's the operating Voltage and Current rating of your relay. Relays under 5V are not common. Chris
  20. CDRIVE

    electromagnetism

    I don't think what you're attempting to do is clear. If you're trying to use an SMD inductor as an electromagnet it ain't gonna happen in this world. Though it may move a compass vane! :) Chris
Top