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  1. BobK

    High Low logic

    What you are saying makes it sound like the adjust pin is an output. It is not, it is an input driven by a voltage divider off rhe regulated output. Saying that it will always be 1.22V is really saying that the output is at the regulated voltage. If the input is too low so that it drops out...
  2. BobK

    DC currents through Rd and Rs in JFET amplifier

    They are the same because the only other connection to that network is the gate which is very high impedance. This applies only if there is no load connected at the drain. If there is a load, its impedance would have to be taken into account. Ohms law applies, in that the current through the...
  3. BobK

    The new types of IOT

    I am not a security expert, my expertise is in compiler development. But, I think the biggest problem with security is people. We are too lazy to take security seriously. I tend to use the same password everywhere for instance. I think biometrics or even embedded chips to uniqely identify...
  4. BobK

    The new types of IOT

    Who do you think you are talking too? As a principal software engineer at Intel until I retired last year, I was quite on the leading edge of technology. I just don't think it wise to open up critical infrastructure to hackers in Kazakhstan. Bob
  5. BobK

    High Low logic

    A comparator is the only thing that will do this sharply. There might be charging ICs that output a low voltage cutoff signal. Bob
  6. BobK

    High Low logic

    A single transitor cannot turn on and off shaply based on a voltage. You need a comparator to do this well. And you need a voltage reference to compare to. On the other hand, you should be using a battery with a built in protection circuit that prevents over charge and over discharge. Bob
  7. BobK

    Help with increasing the power of a Philips hue bulb Frankenstein "hack"

    Do not do that! The controller board is controlling the current going to the LEDs. Using a relay to directly connect the mains would cause the LEDs to go out in one bright flash and possibly set your house on fire. Bob
  8. BobK

    Lcd screen controller board overheating?

    That is a power device, probably a voltage regulator. It might be normal for it to get hot. Bob
  9. BobK

    PwM using microcontroller

    Depends on the frequencies involved and the accuracy required. If slow enough, you don't need any hardware peripherals. Bob
  10. BobK

    Accuracy of digital multi-meters?

    With resistors that high, the impedance of your voltmeter comes into play. Bob
  11. BobK

    Parallel help

    If each turn shorts to a turn of the other coil, you have no coils and the resistance is essentially that of the leads. Bob
  12. BobK

    How to wire up this ssr i have

    Look at the picture, it is a DC SSR. Do not connect AC to it. Bob
  13. BobK

    The new types of IOT

    The same ones that would allow access to voting machines and nuclear power plants? Bob
  14. BobK

    Information on wiring a 5vdc fan and a 6vdc pump in a circuit

    Okay, that makes sense. Even better would be to measure the coil directly if you could get to it. Bob
  15. BobK

    Information on wiring a 5vdc fan and a 6vdc pump in a circuit

    Isn't that what an Ohmmeter does? Not arguing with you, but I would like to know why and Ohmmeter would be unreliable. Bob
  16. BobK

    Information on wiring a 5vdc fan and a 6vdc pump in a circuit

    Unless, of course the motor might be mechanically stalled, then you get the start up current continuously,. Bob
  17. BobK

    How to wire up this ssr i have

    Do you have a link to specs for the SSR? If I had to guess, you need power + and - the DC+ and DC- inputs, and CH1 would be the output from the sequencer. No idea what voltage it want though, you need to know that. Bob
  18. BobK

    Oscillator

    "Four legs good, two legs bad," or maybe: "Four legs good, two legs better." Bob
  19. BobK

    Help with increasing the power of a Philips hue bulb Frankenstein "hack"

    I have no idea what control board you are talking about. I looked up Phillips hue bulbs and they are designed to replace a normal bulb. The controller is inside the bulb. Edited: OK, I reread your original post and now I understand what you are trying to do. You have taken the controller...
  20. BobK

    Help with increasing the power of a Philips hue bulb Frankenstein "hack"

    That is because it became clear you wanted to increase the brightness of a bulb beyond what it is designed for. You cannot do that without severely shortening it's life and perhaps causing an safely issue. Bob
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