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    Woo-Woo Dear Sir/Madam I live in canterbury kent united kingdom

    Check it out. You got quoted on his website. Seems your comment earned you the title of "troll".
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    Frustrated

    No apology required. We have all been there. Enjoy.
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    Frustrated

    The schematic in the video shows 100,ooo Ohms, 470,000 Ohms and 270 Ohms. He says "hundred kill-ohms" if you listen carefully.. With much smaller resistors as you have used, the flash rate will be very high. About 1,000 times faster. If it is robust, you could try moving it, or your head to see...
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    Frustrated

    Check that you don't have two of the resistors swapped. It looks as if you might have Ra and Rb swapped. From memory this would just change the timing, and not cause the symptoms that you suggest. I can't see your images so well, but I can't make out a colour on the last bands of the resistors...
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    Understanding signals in PWM

    Not really an expert at this S-version PWM, but one thing the pulse width modulator must do is decide when to turn on and when to turn off, or when should be high and when should be low. Usually pulses have a fixed frequency and one controlls the width, the time the pulse spends high and low...
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    Circuit with an integrated FLIP FLOP

    Your original description does not seem to have any concept of time. That is, some aspects are instantaneous, these input cause that to happen, others ate remembering state until something happens. Your circuit appears to have a one-second timer in it. Not clear that his has anything to do with...
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    Another Newbie question about Power supplies

    Why? If you are simply trying to power something that normally uses a nine volt battery, then set the voltage to 9 volts. The current will just be what the circuit needs. Power supplies often offer a current limit that helps prevent accidents if connected incorrectly, or circuits are not as...
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    COVID-19

    Oz 5,136 cases
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    Field effect transistor

    It appears that someone who set this homework thought it was a good idea for students to derive the relationship themselves. I do remember this as an effective way of understanding, myself. Policy here, which I agree with, is to not cheat students of the learning opportunity that goes with doing...
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    Field effect transistor

    So, is it only the "short-channel" case that's giving you trouble? For the normal case, I guess both cases, I guess I'd start by looking for the correct answer, so I know what it is that I'm trying to derive. Is that where you're up to?
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    Field effect transistor

    Ok, sorry about that. The problem was Derive .... things What's your progress? Which part do you need help with? Do you have that "basic electrostatic considerations" reference sorted out? Do you have an idea of what an FET looks like, semiconductor construction-wise?
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    Field effect transistor

    How far have you got so far? What's your starting point? Any relevant relationships?
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    Can someone make one of these

    Google the product? I couldn't find it. Price? More than you expect. :) . Technology-wise, would seem that similar would be relatively straight forward, but would need a bit of experimentation to get things right. That means developer time and cost. The mechanics seem simple, but it'd be a bit...
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    Covid 19 tech help solve the virus transmission

    Did you want one, or a product launch? Ok, firstly, check out recent posts. This sort of thing got a lot of comments recently. many of them indicating how difficult this approach would be. Put "covid" into that search bar at the top right. Secondly, check these guys out: Acconeer & A111 radar...
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    555 timer

    From memory, the idea of charging and discharging the timing capacitor from the output, pin 3, is a good way to get virtually symmetrical on and off timing. As the normal charge path can be controlled with resistance to the rail and the discharge path through pin 7 can have resistance inserted...
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    COVID-19

    Yeah, actually I thought about the crew at the time too. Didn't hear much about them. Our man had a balcony, could look out on the reporters and such and get some fresh air.
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    COVID-19

    *Steve*, Hang in there. My team leader was the first local to be positive on the Diamond Princess. He said that for him it was more mild than normal flu. His son didn't even slow down. Just watched TV through the whole thing. Maybe avoiding the cabin fever is the manin thing. :)
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    Parts needed?

    Quick answer (But I did not follow the other discussion, so maybe better there) . No easy electronic way, no. Any solution would be expensive and/or unreliable. . Handcuffs. Tethers to belt. Smelly stuff on hands. Spiderman suit.
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    Determining AM transmitter power output

    If you buy a meter, such as a bird, some measure power into a load, so you need to installl them in line, with a matched load, or the normal load, eg antenna.
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    Stupid question about Resistors

    Sometimes when populating components onto a board, I line the through-hole resistors to all face the same physical direction, as it can look neater. Circuit-wise, like the man says so well above. Either way round: still the same resistor. That's why I can turn them round arbitrarily to make the...
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