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  1. KrisBlueNZ

    Help with Skin Resistance Output

    LOL! Kris
  2. KrisBlueNZ

    Last night...

    Actually I mainly like his 80s stuff. One Trick Pony soundtrack - massively groovy. Steve Gadd (drummer) is amazing! And that beautiful electric piano... I think they're amazing. Jack of Speed (from Two Against Nature) is just SO polished and groovy! Nice enough, and he sure has written some...
  3. KrisBlueNZ

    Multiple LEDs to a single PC power supply

    No, that's a different kind of Berg connector. I guess Berg make a lot of different types too :-) What I'm suggesting is a dual row of pins, of the type that's used on PC motherboards for the connections to the front panel components (LEDs, pushbuttons, speaker etc). These are more generally...
  4. KrisBlueNZ

    Help with Skin Resistance Output

    No worries Chris. We all make mistakes, and we hate it when it happens :-)
  5. KrisBlueNZ

    100VDC bus & arcing connectors?

    I see. So the fixture includes a switching supply that powers the LEDs. Just as an aside, if you're always running the fixture from 100V DC, and there are 23 LEDs in series in the fixture, wouldn't it be possible to omit the switching supply and just use a dropper resistor? I guess there's some...
  6. KrisBlueNZ

    Multiple LEDs to a single PC power supply

    LOL! Those "connector strips" aren't connector strips. That's the way the little terminal inserts are shipped - all attached along a metal strip. You're supposed to cut them off individually when you insert them into the plastic connector shell. What you've done is alright of course, provided...
  7. KrisBlueNZ

    Help with Skin Resistance Output

    Agreed, Harald. Perhaps the best approach would be to reduce the shunt resistance and increase the op-amp gain, then slash the bandwidth by adding a capacitor across RF and increasing RF and RG. This would make the op-amp's input offset voltage more critical, but the bandwidth unimportant. He...
  8. KrisBlueNZ

    Help with Skin Resistance Output

    I don't think it will provide any better common-mode rejection than mine. It doesn't use a differential input, even though there is a differential amplifier there - the inverting input of the differential amplifier is just biased at half the supply voltage, via R2 and R3. So it doesn't have any...
  9. KrisBlueNZ

    led-light-on-your-bag

    Actually Bob, I have even older prior art: in 11,234 BCE, my ancestor Zog put his fire pot into his leather apron for his hike from his cave to the Second High Mountain!
  10. KrisBlueNZ

    rain warning device

    A photo of the failed unit might help.
  11. KrisBlueNZ

    Sending a voltage signal upon receiving another signal

    Hi Harry, Let me try to clarify what you want. Your circuit is to be added on to a printer, to simulate the behaviour of a motor and two optointerrupters. There is also a signal from a hall sensor. The simulator circuit has the following inputs and outputs: 1. Motor: input to simulator...
  12. KrisBlueNZ

    Last night...

    KJ6EAD, thanks for the pointer. I will check it out when my monthly data allocation comes round :-/ poor mystic, I'm grabbing some Stockhausen now to check out. I hope it isn't too... weird! In my high school music class, one of the pieces we studied was by a Polish composer called Penderecki...
  13. KrisBlueNZ

    led-light-on-your-bag

    Hey, I put a light on my bag about twelve years ago! It was for safety when cycling. I'm gonna sue you for copyright infringement! LOL
  14. KrisBlueNZ

    Bernoulli Binary Generator

    Did you do your Due Google Diligence? I found http://www.scientific.net/AMM.152-154.1869
  15. KrisBlueNZ

    Trying to make analogue sound to lcd?

    Good arguments, and well expressed. It's certainly true that the people on this forum have not done a lot of investigation into so-called EVP, but other people have, and when they have strictly applied the scientific method to the claims, they have concluded that there is no credible evidence...
  16. KrisBlueNZ

    Help with Skin Resistance Output

    I don't see why you need such a complicated circuit. A bridge, feeding a differential amplifier... All you need is a source of current and a buffer or gain stage. Just one resistor, one set of contacts, and one op-amp. (A couple of protection diodes would be a good idea too.) A simple circuit...
  17. KrisBlueNZ

    High Power Dual H-Bridge

    SORRY for the slow reply! I must have missed your question. No, with the LMD18200 you need to use PWM because the output stages need to be switching on and off regularly to pump the charge pump that provides the gate bias for the top MOSFET. That also means you need to keep your PWM range...
  18. KrisBlueNZ

    why 1K resistor

    I agree, that's not a very good design. It's also incomplete; you should show the circuit that provides the base drive signals. Nowadays, H-bridges are normally made using MOSFETs. They draw relatively little bias current, and can have extremely low ON-resistances, so they waste almost NO power...
  19. KrisBlueNZ

    Multiple LEDs to a single PC power supply

    Am I right to assume that you want these LEDs to illuminate the different parts of a computer, with a transparent side panel? It depends on how you want to support the LEDs. A common construction method is stripboard (also called veroboard) - Google it, and you'll see what it looks like. LEDs...
  20. KrisBlueNZ

    100VDC bus & arcing connectors?

    I don't see why there should be any significant arcing. LEDs are not inductive. The current into each fixture is only 100 mA. If there is any arcing, it will only occur on connection and disconnection (mainly on disconnection). How often are you planning on connecting and disconnecting each...
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