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    Continuous measurement between two points approximately 2.5m apart

    Presumably there is something obstructing the direct path? Got a brand, model number and/or image?
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    Oddball electric fence charger.

    Google for electric fence energiser circuits. You'll get lots of hits. The articles will give you a better idea fo what has to happen to make them work. One of the first I got was As above; the high voltage is a result of the coil primary-side current changing suddenly. The spark in the car...
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    Creating an alphabetized list

    I think we have tried to help. There may be a learning curve with all products, apps. For the ones suggested it is modest. Many spreadsheets allow you to add new rows on the bottom, then without programming, choose to view by sorting by any column, often by just clicking at the top of the...
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    Creating an alphabetized list

    Tried Google sheets? Open/libre office Spreadsheet? Excel?
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    Electrical Circuits

    Cannnot read all your answers. Might want to check exercise 1.4. It might provide more insight.
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    Managing parallel loads in 12v circuit

    Ok, I will try again. "isolate" is not a fruitful direction, for any interpretation that I think likely. Load currents add. You must supply the sum of them. I try to explain, below. . Sounds as if your bench supply cannot supply the current required by the combination of both circuits. If one...
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    Managing parallel loads in 12v circuit

    Probably want to look at it a little differently. . You are correct in that if the supply stays as 12 volts, it should make each or both in parallel go. Most likely when you have both connected, the total load is greater than the supply allows; that is the total current is greater than the...
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    Please help an absolute beginners with LEDs

    Can you give us the description, or a supplier and part number for the led strip. It appears to have only +5, R, G, B without the usual ground connection. Is there a GND connection on the back of the strip? If not, it may be that the R, G, and or B need to be connected to ground (supply...
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    RS422 Help

    The use of the word "data" suggests that you should first revise serial communication.. Search for tutorials on serial communication. eg https://learn.sparkfun.com/tutorials/serial-communication/all . Serial communication sends bits one after another. After synch has been acheived, at certain...
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    P=I^2R formula confusion from book

    Not sure what you are missing. The text says by lowering either the current or the resistance. For the simple relationship of P changes linearly with R, what is the implication for I? In the first equation, examine what the voltage must do if the current I is to remain constant as you change R...
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    Non zero output from LM358 even though input is zero

    Can't say that I am an expert on the LM358. Looking at the datasheet it gives a typical high output level of 3.5 volts, if VCC is 5volts. This seems to indicate that the output level you quote might be the high output: that is, as high as it goes. . Your circuit didn't seem to post. Maybe try...
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    Tesla coil between Lego base plate

    Sorry if my message before was not clear. Yep, can be done with a single-sided board & a single wire to the middle, or a double-sided board. The bifilar thing is not particularl;y relevant. Just a simple coil wil do if you use a PCB. Notes Yes, for magnetic field the current should all go...
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    Tesla coil between Lego base plate

    I suspect the bifilar thing is a bit of a red herring. Probably can wind it with any wire you like, multi-core or not. Amperes (current) and turns are what will matter; also area, but fixed by the area you want to cover. So, multi-core cable just sometimes makes it easier to wind, but each two...
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    Tesla coil between Lego base plate

    The i-brix site says thattheir technology is inductive, which makes sense to create a magnetic field. If your coil in the bottom is low resistance it won't get hot. The more turns, the lower the current you;ll need.The lights need to likewise pick up the magnetic field, so, a small coil, maybe...
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    Tesla coil between Lego base plate

    Sorry, just catching up on what I think is going on. A man called Tesla patented bifilar coils. From the text, I assume he worked with inductive coils, possibly also non-indiuctive. He also has a high voltage transformer style named after him, commonly known as a "Tesla coil". . The linked coil...
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    Tesla coil between Lego base plate

    This page https://en.wikipedia.org/wiki/Bifilar_coil Seems to include something they call non-inductive and inductive bifilar coils. The one you linked looks as if it might be non-inductive, which I'd guess will not excite a tesla coild much. There's a figure on how an inductive bifilar coild...
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    Tesla coil between Lego base plate

    I may be interpreting the image incorrectly, but it seems that the current goes into the center in one direction, say clockwise, then back out again, anti-clockwise. This would seem to mean that the net magneticc field will be very low. . The ones I've seen have either two sides, so the current...
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    Tesla coil between Lego base plate

    MIght be viable and safer to google "magnetic induction" and maybe other forms of pancake coils. Would make the lighting blocks a little more complicated, maybe even with a little ferrite, but generally easier to control. . I'm biased. I can't see how a bifilar coild as illustrated generates...
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    Can PIC microcontrollers be equipped with NFC modules?

    BLE is convenient. You have a choice of using modules that simply look like uarts, or for the more adventurous, other BLE services. Is power an issue at the PIC end?
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    Single Led flasher circuit.

    UJTs are not really a modern component, but 2N2646 is still relatively common, I suspect. There are also flashers based on bipolar transistors that are almost as simple. . If you don't mind winding a coil, there's also something called a Joule thief.
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