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  1. N

    4 USB Ports Switch For 6 Computers

    Not quite clear on your approach. You plan to swirtch the power lines with the FETs? You plan to have all the data lines go to the micro and just use the ones for the selected device? Or do you want to have just one set of data lines and switch them to multiplex them too? . If your question is...
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    4 USB Ports Switch For 6 Computers

    Homework? There is a dedicated forum for help with that. Switching lines? Not sure that you will need 1000 volt and 3.Amp to switch the data lines.
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    On a D.C. power supply.

    Jeff, not sure what you are missing or wanting. . If I have an isolated 5 volt supply, I can treat the negative as ground, zero volts, if I like and the positive as +5 if that suits me. If I have an isolated 12 volt supply, I can do the same. If I now connect the negativbe of the 12 volt supply...
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    Looking for 60A 60V mosfet

    Or to put the same question another way: in what way did the previous FETs not work?
  5. N

    On a D.C. power supply.

    Theoretical question, or do you have something practical in mind? Some supplies and other equipment have a terminal actually connected to ground, though most bench supplies let you choose, by having the outputs "float". If you're planning to connect one or other of the outputs to a real ground...
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    diode question

    For MOSFETS, at least in the first approximation, parallel is ok as RDS(on) has a positive temperature coefficient. I found https://assets.nexperia.com/documents/application-note/AN11599.pdf - for mosfets . For diodes with the negative coefficient, it will rely on the match being better and the...
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    diode question

    I always thought that the main effect would be forward voltage decreasing with temperature rise. That is, as the diode taking more current gets hot, it takes more current. Net result even more uneven sharing and potential destruction, one at a time. Not done the math. Do not know which effect...
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    Identify capacitor value - short part code

    Yeah, thanks for the confirmation. Expecting that will not be the end of it, but already up and running on the other one, so thought I'd have a look at checking and replacing some bits.
  9. N

    Identify capacitor value - short part code

    Image, hopefully attached, shows an ex-capacitor. Can you confirm the specs? . ADSL modem, on during a thunder storm (rare here). Input capacitor, at least, no longer intact. . Assembled, just over 1cm lead to lead. . Part shows F683J t 630MPP1 Part numbering found online for MPP capacitors...
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    British Television?

    Wow ethics :) The right to interpret signals or data? Big topic.
  11. N

    Want to get a cheap oscilloscope(advise)

    What was it that you wanted to use it for? Marine radio RF? What sort of frequency is that? Generally the "bandwidth" of the scope determines the upper frequency you can use it on. Apologies if I explain the obvious, but what "bandwidth", frequencies are you dealing with? In my area we only...
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    Can integer variable store char value?

    What result did you get when you ran it? Seems as if you are doing the right experiment to test the idea. Most languages use ASCII which means that a character is 8 bits long. It's a convention of representing characters as numbers, since in computers we really only have bits and numbers and...
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    British Television?

    New Zealand: TV licenses and detector vans disappeared about 1999 here with privatisation of the networks. Was capped at $100 per year. (1999 dollar value).
  14. N

    how much current from RS422 output.

    Not really an expert at RS422, but Google is a really helpful guy to have round. https://www.electronics-notes.com/articles/connectivity/serial-data-communications/rs422-basics-tutorial.php Says RS422 specifies an output current of 150mA The fault protected MAX14775 says it protects at 200mA...
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    Recommendation for a noob.

    Just a side note for the future. Arduino sketches are almost C. If you get up to speed on arduino using the environment, it's fast, plentiful examples, but remember that is is a somewhat simplified C language, not having traditional header files and such. For you to gain protability as a C...
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    Do I understand what this does ?

    The description that they provide seems to verify that it what you suggest. It appears to be a toggle flifp-flop with a mosfet output driver capable of a few amps. Not rellay sure what I'd use one of these for, but maybe others have ideas. I guess my first thought is that it provides you with a...
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    Need Guidance (not-spoon-feeding) on self-Learning Embedded System development to get a Job

    Areas for embedded design? IOT - opencv images, cameras. Add python. Learn to connect to the cloud and cloud services. Add experience with woreless commns. Cloud services can be cheap: not so bad to get experience. IOT is still on a roll. Edge processing is starting a comeback, promoting things...
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    Can I replace PLC with microcontroller for project

    Some PLCs do a lot of conditioning of inputs for you. For example, you tell it that you only want to create an event when some signal changes beyond a particular amount, or out of some control zone. Some also have support for various commonly-used functions. The standards define multiple ways to...
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    Random noise prank

    If you want small and discrete, have a look at the ISD1820. It may have cousins by now. I have not looked in a while. Multiple track, recorder, playback. eg https://www.instructables.com/id/HOW-TO-USE-ISD1820-VOICE-RECORDER-AND-PLAYER/ Some have made these sorts of thing light-sensitive, to...
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    MCS-51 compatible software burner help

    Not smething I've used lately. Are there parameters to set in programming? Googling found similar messages, eg https://www.avrfreaks.net/forum/avrdude-warning-cannot-set-sck-period-please-check-us Which talks about "You need to set the programming clock NO FASTER than 1/4 of FCPU of the target...
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