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  1. N

    Senior Project

    What are your skills? What sort if thing have you done so far in engineerring class? Let us know your starting point. Could be app on phone talks to bluetooth module in pillow with vibration motor attached. Is that the direction you were thinking? . I guess you could set the phone to vibrate and...
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    Pcb as antenna track

    Matching usually needs equipment and experiment. Look for an app note?
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    Stumped on this circuit blinking led with 1 transistor

    If you want a reliable flasher in one transistor, check out "UJT". :)
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    Early 1970's Fairchild Transistor Question

    Similar info available at https://archive.org/details/FairchildSemiconductorTransistorAndDiodeCondensedCatalogOctober1971
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    Active high signal

    What are the positive power supplies on the PIC and the IC? Are they on the same board? Sharing the same negative rail?
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    12v EL glow wire

    It's never seems as bright as the images and as shown, some colours are brighter than others. But it is fun.
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    12v EL glow wire

    The only electroluminescent wire I've used used a low voltage supply, but had a step up converter to higher voltage. That is; the small box sings when running. :) I've seen multiple references to cutting it. Google it. Just now I found https://www.instructables.com/community/can-you-cut-el-wire/...
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    IoT web application

    Give us an idea what you want to achieve? . The last proof of concept I did went like this; IOT device Bluetooth (BLE) beacons - talk to BLE gateways, which talk MQTT over wire, or Wifi, to a MQTT broker. The node running the MQTT broker also uses python for processing and python flask to...
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    automatic storage classes

    https://stackoverflow.com/questions/4688816/concept-of-auto-keyword-in-c According to this page "auto" is the default we use freely as it is the default scope. It contrasts with others such as "static". So, there is no difference between using the default which is "auto" and explicitly using...
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    Function returning pointer

    Not entirely sure which aspect is causing you the problem. Is it the passing back of the pointer (the address)? In your code you create a temporary variable, "x", local to your function, and then pass this address back, as if it were still valid. As the function exits, this location becomes no...
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    Wi-Fi Beacon Photo or Plot?

    You can check the specs, but from memory it's just another wifi packet. It is sent, by default, once every 100mS. So apart from it having a small payload, hence brief in time, I presume that it just looks like other wifi packets. With QPSK the data is represented by phase shifts on the carrier...
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    Are UJT's used anymore?

    I have not tried to buy ujts since 2015, but they (2n2646) were $16 for a bag full on aliexpress at that time. A much underrated device in my opinion. :) And, yes, I too bought attinys more recently, but not for the same jobs. A quick search suggested 2N1671 listed at about $7 for ten.
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    home windmill reconfiguration questions

    Sorry, I think a typo or auto-correct got your last line. . The energy out is never going to exceed the total energy in. Any generator rating will be spec'ed at an input sufficient to create that output. If a generator is spec'ed at 2000 watts at optimum speed, then it's going to take more than...
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    Wi-Fi Beacon Photo or Plot?

    Several cycles? . Can you clarify? You want the time waveform? As SS carrier with modulation, or individual cycles of RF showing QPSK? . You want several beacon packets? I guess as you suggest, they are usually sent every 100mS. But, I think they are just wifi packets, from memory, being...
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    home windmill reconfiguration questions

    Short answer: Sorry, not going to work. Output cannot exceed input. Electrical power in to fan some losses in fan motor Fan converts electrical power to rotation of vanes which moves air some looses in conversion to wind Your windmill vanes pick up a proportion of this wind energy some losses...
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    Lighthouse project, flasher relay

    A real electromagnetic relay might not be the best choice. A solid state solution might be lower power and not mind a large number of switch cycles. Also, LEDs are likely more efficient than a real "bulb". I googled [lighthouse flasher] and [solar lighthouse flasher] and found a few people who...
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    Flooded Circuit Board Repairs

    No idea about the US phone system, but some places have had changes over time between 2-wire and 3-wire systems, which affect how the ringer signal arrives. I imagine if a phone expected the ring signal in one place and it arrived elsewhere it might not ring. May I ask whether this has been...
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    'Human body only" sensor

    Are the humans in view wanting to be detected? Or for example, not wanting to be detected? Give an idea of what's going on?
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    Capacitor with conductive metal inbetween plates

    C = k A/D - first capacitance, where "k" relates to the dielectric. Here air. Later two in series as Harald Kapp explained above. C = C1 in series with C2, but each now has a much smaller "D" as you are filling the space up with conductor. . So let's say I half fill the space, D, by choosing an...
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    NAND logic gates - feedback

    Did you find a name for the circuit? You may find similar circuits online with a generic name for this tuype of circuit.
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