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9Instructables529,293Views298CommentsSecret desert proving ground, located somewhere in the Former United States, Southwest region.Joined May 11th, 2008
I've built some weird stuff over the years, but most of that stuff has remained unseen by the world outside of me and a few friends. But then one day, one of these friends, he says to me, "Hey Jack, you should take some pictures of that weird stuff you're building all the time, and uh, I don't know, like, put those pictures on the internet or something..."

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  • Seems contradictory. I thought the whole point of Instructables, was projects that could be repeated.The phrase, "Don't try this at home." I dunno. It's kind of reminiscent of television, like back in the days when videos were only produced by big money TV and movie studios, and when the announcer said not to try this at home, those words were often followed up by more words, for to convince the audience that the people performing this stunt really were professional, well trained, well equipped, know-what-they're-doing, professionals.By the way, there is a phrase often uttered in unprofessional settings, that sounds a little something like this,"Hold my beer. I'm gonna try something."Have you heard that one before? Maybe Instructables should have a HMBIGTS contest...

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    Seems contradictory. I thought the whole point of Instructables, was projects that could be repeated.The phrase, "Don't try this at home." I dunno. It's kind of reminiscent of television, like back in the days when videos were only produced by big money TV and movie studios, and when the announcer said not to try this at home, those words were often followed up by more words, for to convince the audience that the people performing this stunt really were professional, well trained, well equipped, know-what-they're-doing, professionals.By the way, there is a phrase often uttered in unprofessional settings, that sounds a little something like this,"Hold my beer. I'm gonna try something."Have you heard that one before? Maybe Instructables should have a HMBIGTS contest. ;-P

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  • Jack A Lopez commented on 500FPS's forum topic UPS battery backup as car inverter?2 months ago

    Yeah. I think that would work. In fact, I think I have all the ingredients for this recipe myself.I mean, I've got a car that will start, and I have a small pile old UPSes. I've got wire, and solder.I should try this, and report back.

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  • Wow! I am glad I could help you somewhat, in your efforts to find, CONNECTING ROD!Also, there is something about this topic that reminds me of an old episode of The Simpsons. Perhaps Frinkiac.com can help me find it. It was another example of a thing named, ROD, saving the day. I think they even gave ROD an award. Ah, yes! Here it is:"Deep Space Homer" Season 5 / Episode 15 (1:49)SO, A ROUND OF APPLAUSE FOR... THIS INANIMATE CARBON ROD. [ Cheering, Whooping ]https://frinkiac.com/caption/S05E15/109191

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  • Well, it is hard to guess, but the instructions,http://www.homedepot.com/catalog/pdfImages/2e/2e14...found in a link on the page you link to, mention something called "connecting rods". Specifically, in Step 3,Step 3. Insert the the connecting rods on each Arm/Hand ( C.D ) into the Upper Section of Tree (A).(FIG.3)I am guessing that there is one for each arm, and I am impressed that you've managed to loose both of them. Or do you have one, but not the other?You keep referring to it using singular language.I need that plastic piece, I hope someone somewhere knows what its called and hopefully where it is.Regarding the question of "where it is", I think the place to check first is in the pile of discarded packaging that came with this artifact. If the missing part i...

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    Well, it is hard to guess, but the instructions,http://www.homedepot.com/catalog/pdfImages/2e/2e14...found in a link on the page you link to, mention something called "connecting rods". Specifically, in Step 3,Step 3. Insert the the connecting rods on each Arm/Hand ( C.D ) into the Upper Section of Tree (A).(FIG.3)I am guessing that there is one for each arm, and I am impressed that you've managed to loose both of them. Or do you have one, but not the other?You keep referring to it using singular language.I need that plastic piece, I hope someone somewhere knows what its called and hopefully where it is.Regarding the question of "where it is", I think the place to check first is in the pile of discarded packaging that came with this artifact. If the missing part is small, maybe it fell in with that trash.Or maybe it is in between the couch cushions?If you have this part on one side, but not the other, I would suggest trying to sort of make a crude copy of that part, for the other side, using whatever materials you have available, like steel coat hanger wire, or wood popsicle sticks, or whatever.Actually, even if this part is missing on both sides, and we do not know exactly what it is supposed to look like, maybe you could fill in that part with your imagination. I mean I think there are just a few parameters, like: How long is it? How big are the holes (connectors) on each end?By the way, I could not help noticing that Wikipedia has an article titled "Connecting rod", https://en.wikipedia.org/wiki/Connecting_rodand of course that is some very general information, but who knows? Maybe that could serve as some inspiration for you.

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  • I had not heard that one before. That joke is almost as funny as the one about the chemist who says, "NO," when asked if he or she can remember the formula for nitric oxide.http://www.lukesurl.com/comics/2010-12-01-chemists...;-P

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  • Well, this is quite a story, or maybe it is poetry, an ode to hydrogen peroxide (H2O2). Let us count the ways, that this compound is useful for stuff.Everything you write here is true, and I do not suspect any bias, like I would from a web site for a business that sells H2O2.Although it kind of makes me wonder. Have you recently got into the hydrogen peroxide selling business?The other thing I was going to say is that whatever you have written about the availability, and legality, of the higher concentrations of H2O2 for sale in your country or region, likely only applies to that region.I mean, in my country, the former United States, it is easy to find 3% in stores, sold as disinfectant. It looks like 12% and %27 can be found on eBay, at the time of this writing. Although I'm not s...

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    Well, this is quite a story, or maybe it is poetry, an ode to hydrogen peroxide (H2O2). Let us count the ways, that this compound is useful for stuff.Everything you write here is true, and I do not suspect any bias, like I would from a web site for a business that sells H2O2.Although it kind of makes me wonder. Have you recently got into the hydrogen peroxide selling business?The other thing I was going to say is that whatever you have written about the availability, and legality, of the higher concentrations of H2O2 for sale in your country or region, likely only applies to that region.I mean, in my country, the former United States, it is easy to find 3% in stores, sold as disinfectant. It looks like 12% and %27 can be found on eBay, at the time of this writing. Although I'm not sure about the purity of the %27 one. That one is a "chlorine free pool shock" kind of product, and the fact it contains %27 H2O2 is only to be found in the fine print, strangely not something the seller wants to brag about.The odd thing about many of these eBay listings is that it looks like people are looking for 35% H2O2, but nobody is actually selling it. Yet the listing titles include the asinine phrase, "dilute 35%", (logically equivalent to "not 35%") just to catch the eye of people searching for the strong stuff.e.g."8 oz 12% FOOD GRADE HYDROGEN PEROXIDE (dilute 35% h2o2) (MAKES 32 oz of 3% =2pt)""HydroProx 35 (TM) - Pure 35% Food Grade Hydrogen Peroxide (Diluted to 8%), 4 oz"In fact on Youtube, there are numerous amateur chemistry videos showing us how to make the dilute stuff more concentrated, e.g. by gentle boiling. The water (H2O) part seems to be more volitile, comes off first when trying to boil it. Of course the reason these videos exist, is because the repressive FUS government, and others, wants to protect their subjects from dangerous chemicals, or terrorists, or something.Anyway, I thank you for telling us all about the wonderful uses of hydrogen peroxide.If anyone wants to drag this topic in a different direction, some places to go include:-o- Ways to concentrate weak store-bought H2O2 to make it stronger.-o- A way to make H2O2 from the dry distillation of sodium percarbonatehttps://en.wikipedia.org/wiki/Sodium_percarbonate By the way, I have no idea if the process for that would be easy or hard, but think that stuff, sodium percarbonate, can be found in stores in the former US, and also it is a dry powder, which stores well.-o- Other homemade oxidizers with potential use as disinfectant, bleach, etc.For example, ozone can be made easily from air and electricity. Maybe nitrogen oxides can be made from electricity and air also. I am sure I have seen homemade Birkeland-Eyde machines, on the internet (OTI).Also homemade chlorine bleach via electrolysis of salt water. Also homemade... every chemical! Have you seen sciencemadness.org? I think they have a wiki too now. They used to be just a forum. The reason I mention that site, is because if you are ever contemplating what would be involved in the homemade synthesis of, whatever, and the related question of, has any amateur ever done this successfully, and are there pictures?;-PWell then look no further than sciencemadness.org. I mean just include the phrase "site:sciencemadness.org" in your search query, like this,https://duckduckgo.com/?q=potassium+permanganate+s...Potassium permanganate, KMnO4, that's another good one. Rumor has it, this compound used to be available, in dry solid form, sold as a cheap, concentrated, disinfectant. Wikipedia mentions the brand name, "Condy's Crystals"https://en.wikipedia.org/wiki/Henry_Bollmann_Condyhttps://en.wikipedia.org/wiki/Potassium_permangana...but I have never actually seen KMnO4 sold as a disinfectant. I've seen it sold as a reagent for water treatment, for, "greensand", type water processors. That stuff is not sold everywhere in the FUS, but likely only in stores in geographic regions that have that particular kind of bad water, necessitating a "greensand" filter, and also eBay for those fortunate enough to live in geography with better water.It makes me think, there might very well be regions in the FUS with naturally soft water, where the stores do not sell "water softener salt", (for ion exchange water softeners). That is of course the best dollar per kilogram price I've seen for (mostly sodium chloride) salt, or potassium chloride. Maybe that sort of thing is even cheaper for people who live near the ocean? Neglecting the cost of drying it, and tossing out the seaweed.;-P

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  • Jack A Lopez commented on fosgate3's forum topic Can I add a pot? 2 months ago

    Someone was asking the answers forum about this one, just the other day, here:https://www.instructables.com/answers/Add-on-radio...Typically, putting a resistor in series with the speaker is the trick for making a too-loud electronic gizmo be more quiet.The tricky part to this trick, is figuring out the approximate size of the resistor needed, which is maybe why you want to use a potentiometer; a.k.a. pot; i.e. a variable resistor. However the range over which a pot is adjustable is not huge, like zero to infinity ohms. It is more like 0.1 to 1.0 multiplied by the full value; e.g. a 100 ohm pot is practically adjustable from like 10 ohms to 100 ohms.Anyway, starting out, it is hard to guess how much series resistance will make the sound as quiet as you want. So you start out with some...

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    Someone was asking the answers forum about this one, just the other day, here:https://www.instructables.com/answers/Add-on-radio...Typically, putting a resistor in series with the speaker is the trick for making a too-loud electronic gizmo be more quiet.The tricky part to this trick, is figuring out the approximate size of the resistor needed, which is maybe why you want to use a potentiometer; a.k.a. pot; i.e. a variable resistor. However the range over which a pot is adjustable is not huge, like zero to infinity ohms. It is more like 0.1 to 1.0 multiplied by the full value; e.g. a 100 ohm pot is practically adjustable from like 10 ohms to 100 ohms.Anyway, starting out, it is hard to guess how much series resistance will make the sound as quiet as you want. So you start out with some actual resistors, not pots, powers of 10, like:1 ohm, 10, 100, 1000,and listen to what those sound like. In the answer I wrote to the question I linked to above, I think I recommended a resistor about the same size as the impedance of the speaker, or perhaps one about ten times the impedance of the speaker .Regarding your question of where to put it, like, on the left terminal, or the right one, or between the speaker and ground ( if the speaker originally has one of its terminals connected to ground)... The answer to all of these is that it does not matter exactly where you put the resistor. All that matters is that you wire it in series with the speaker. Also resistors do not have polarity, so it is impossible to put a resistor in a circuit "backwards".Regarding the question of damage the existing speaker driver circuit, I would expect putting a resistor in series with the speaker, increasing the impedance it sees, will result in it driving less current, and less power. In other words, I expect the driver circuit to be underloaded, doing less work than it was before, and therefore running a little cooler, and happier, than before.

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  • Heh. You said, "suck". So, like, you want to find a fan motor that really sucks! The more it sucks, the better! Amirite?;-PYou know what else sucks? The fact that you asked this same dumb question a week ago, here:https://www.instructables.com/community/Smoking-ma...But you know, feel free to keep littering this forum with the same question asked over and over again, in slightly different ways, until you get, or don't get, an answer that you like. By the way, I read somewhere that Bill Clinton, a former president of the former United States, "had a nose like a vacuum cleaner."https://duckduckgo.com/?q=bill+clinton+had+a+nose+...I'm not totally sure what that means, or if it is relevant to your question, but the stories are out there, for anyone willing to search fo...

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    Heh. You said, "suck". So, like, you want to find a fan motor that really sucks! The more it sucks, the better! Amirite?;-PYou know what else sucks? The fact that you asked this same dumb question a week ago, here:https://www.instructables.com/community/Smoking-ma...But you know, feel free to keep littering this forum with the same question asked over and over again, in slightly different ways, until you get, or don't get, an answer that you like. By the way, I read somewhere that Bill Clinton, a former president of the former United States, "had a nose like a vacuum cleaner."https://duckduckgo.com/?q=bill+clinton+had+a+nose+...I'm not totally sure what that means, or if it is relevant to your question, but the stories are out there, for anyone willing to search for them.

    This is not a bad idea. Although I would add: the act of tossing out the heating elements, will necessitate some other DC power supply for the fan motors, because in the typical cheap (sheap? sheep?) hair dryer, the motor is powered by a kind of cheap-and-dirty rectifier circuit, that actually uses the hair dryer's heating elements as a kind of voltage-divider, for to limit voltage to the motor. The actual power used by the fan motor is DC, and has magnitude of, I am guessing, approximately, (10 volts)* (1 ampere) =10 watts. I mean, this kind of motor, the motor itself, is brushed, permanent magnet, DC. https://en.wikipedia.org/wiki/Brushed_DC_electric_...You can make this kind of motor run at a wide range of speeds, depending on how much voltage you feed to it.

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  • You should try this.By the way, there is word for what you get when you connect a pair of tiny speakers to a headphone plug, and the word for this is, "headphones".In response to your question, "Do I just connect them to a minijack and it'll work?"I think you will get sound being emitted by the tiny speakers, but that sound will not be very loud.To make sound louder, requires device called amplifier.Often speakers and amplifier are packaged together, and the correct name for this package is "amplified speakers".A lot of people are ignorant, and use the word "speakers" to refer to "amplified speakers", so it is often hard to tell exactly what someone is talking, or writing, about, when he or she says, "Well, I've got some speakers he...

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    You should try this.By the way, there is word for what you get when you connect a pair of tiny speakers to a headphone plug, and the word for this is, "headphones".In response to your question, "Do I just connect them to a minijack and it'll work?"I think you will get sound being emitted by the tiny speakers, but that sound will not be very loud.To make sound louder, requires device called amplifier.Often speakers and amplifier are packaged together, and the correct name for this package is "amplified speakers".A lot of people are ignorant, and use the word "speakers" to refer to "amplified speakers", so it is often hard to tell exactly what someone is talking, or writing, about, when he or she says, "Well, I've got some speakers here, that I pulled out of an old computer..."However, if you have the actual artifact in front of you, there is an easy way to distinguish amplified speakers, from just plain speakers. That is, if there is a place to input power, then your speakers are the amplified kind, because amplifiers require input power. Also if you have the cover off, you will see components that look like active components; i.e. chips, sometimes with heatsinks, and usually a little population of resistors and capacitors surrounding those chips, usually all soldered together on a little circuit board.It looks like Wikipedia uses the word, "powered speakers", for what I am calling amplified speakers, here:https://en.wikipedia.org/wiki/Powered_speakersThey also have an article for plain, unpowered, passive speakers too, here:https://en.wikipedia.org/wiki/LoudspeakerAlso if you want to see some different phono plug shapes, there is an article for this too.https://en.wikipedia.org/wiki/Phone_connector_(aud...The headphone plug I see most often is called 3.5 mm TRS (tip, ring, sleve), and I think that is the same thing you call "minijack" or maybe "miniplug", when taling about the plug side. Perhaps if you were talking about the smaller 2.5 mm version, you would call it "subminijack" or "subminiplug"

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  • Does it matter if tape on the inside of the box looks ugly? After all, the inside of the box gets looked at less often than the outside.Also, in the past, I have used glue, the so called "white glue", also called PVA,https://en.wikipedia.org/wiki/Polyvinyl_acetatefor gluing one piece of cardboard to another, for to make a seam in a cardboard box.Actually that re-glue job, was not for a re-sized cardboard box. It was for a turn-the-box-inside-out job. This particular cardboard box was covered with ugly, glossy, garish, advertising, and I wanted to turn it inside-out, so the outside appearance of the box would be plain, brown, cardboard, instead of ugly advertising.The main drawback with glue, besides it being complicated, necessitating some flat pieces of wood and clamps to s...

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    Does it matter if tape on the inside of the box looks ugly? After all, the inside of the box gets looked at less often than the outside.Also, in the past, I have used glue, the so called "white glue", also called PVA,https://en.wikipedia.org/wiki/Polyvinyl_acetatefor gluing one piece of cardboard to another, for to make a seam in a cardboard box.Actually that re-glue job, was not for a re-sized cardboard box. It was for a turn-the-box-inside-out job. This particular cardboard box was covered with ugly, glossy, garish, advertising, and I wanted to turn it inside-out, so the outside appearance of the box would be plain, brown, cardboard, instead of ugly advertising.The main drawback with glue, besides it being complicated, necessitating some flat pieces of wood and clamps to squish the seam together while the glue dries, is that it takes time for the glue to dry.In contrast, the advantage with using tape, is it takes less time and effort, and you can use the box right away.

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  • Such things exist. I recall, one of these relays, made for switching power to electric lights, was made by General Electric (GE), and named "RR-7", and I found a data sheet for this, in pdf, here:https://www.friedmanelectric.com/Images/img/043180...I have an uncle who used to live in a house, for which all the lights, in every room, were switched through a big cabinet of these relays. Also, the light switches in every room were actually low voltage switches, that switched a momentary low voltage signal to the relay controlling the light in that room. Also somewhere in the house there was a control panel, for to switch on or off any light in the house.I think the voltage for these relay coils was 24 VAC.

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  • Well, you know the goofballs who ask questions here. A lot of them can't be bothered to write back to tell us about their success, or lack thereof.In any case, I wish OP well, and I hope he or she did not die as a consequence of risky lawn mower repairs, or because the grass got too high! Ha!;-P

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  • Jack A Lopez commented on LeeS182's forum topic Barometric pressure sensor2 months ago

    Atmospheric pressure decreases exponentially with altitude. The approximate formula for this will look like:P =P0*exp(-z/H)Where P0 is the pressure at height z=0, somewhere on the planet's surface, and heights z>0 are above height. H, which has the same units as z, is called a "scale height". H for Earth's atmosphere is roughly 8 km.Essentially what the equation says, is that for every H increase in height, pressure falls by a factor of (1/e). A consequence of this is, if your pressure sensor has a linear response, (and I think most of them do) then everything above about 4 or 5 scale height, or 32 or 40 km, is going to look like approximately zero pressure.Let me show you what I mean, like with some numbers; e.g. P0=100 kPa, H=8.0 km.P(z=0) = 100.000000P(z=8) =36.78794...

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    Atmospheric pressure decreases exponentially with altitude. The approximate formula for this will look like:P =P0*exp(-z/H)Where P0 is the pressure at height z=0, somewhere on the planet's surface, and heights z>0 are above height. H, which has the same units as z, is called a "scale height". H for Earth's atmosphere is roughly 8 km.Essentially what the equation says, is that for every H increase in height, pressure falls by a factor of (1/e). A consequence of this is, if your pressure sensor has a linear response, (and I think most of them do) then everything above about 4 or 5 scale height, or 32 or 40 km, is going to look like approximately zero pressure.Let me show you what I mean, like with some numbers; e.g. P0=100 kPa, H=8.0 km.P(z=0) = 100.000000P(z=8) =36.787944 P(z=16) =13.533528 P(z=24) =4.978707 P(z=32) =1.831564 P(z=40) =0.673795 P(z=48) =0.247875 P(z=56) =0.091188 P(z=64) =0.033546P(z=72) =0.012341P(z=80) =0.004540I mean it is not going to be a problem to find a pressure sensor that can survive pressures as low as complete vacuum. The problem is getting a meaningful prediction about height from those really low pressure values.

    Hey. I was thinking. There might be other ways of inferring altitude, at those, like, really high places where the pressure drops to nothing.I think there might be something predictable that happens with temperature, also speed of sound, and I have seen graphs of this, here,https://en.wikipedia.org/wiki/U.S._Standard_Atmosp...and maybe other places too.

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  • This topic was posted over four years ago. "...will proceed with my inkling of an idea and tell you how it goes or not!" Then the original poster, he or she, never wrote back. So we are left wondering: How did it go?

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  • Hey, I thank you for giving me a link to an example of one of these, um, what are we calling them? "12V hydroelectric generator" That is probably a pretty good description, for purposes of finding them on eBay, or reviews, pictures, etc, of them on various forums.As I demonstrated earlier, big water towers are not going to be probably not going to be able to compete with a good battery, in terms of specific energy (kilojoules per kilogram) or in the cost of the energy storage like in dollars per kilojoule.Of course the cost gets better, if you can use an existing source of pressurized water. Like municipal water. I mean, in that case, someone else has already paid the expense of building the water tower.So I am kind of curious what kind of tech these new, mass produced, &...

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    Hey, I thank you for giving me a link to an example of one of these, um, what are we calling them? "12V hydroelectric generator" That is probably a pretty good description, for purposes of finding them on eBay, or reviews, pictures, etc, of them on various forums.As I demonstrated earlier, big water towers are not going to be probably not going to be able to compete with a good battery, in terms of specific energy (kilojoules per kilogram) or in the cost of the energy storage like in dollars per kilojoule.Of course the cost gets better, if you can use an existing source of pressurized water. Like municipal water. I mean, in that case, someone else has already paid the expense of building the water tower.So I am kind of curious what kind of tech these new, mass produced, "12 volt hydroelectric generator", things have inside them. I tried doing an image search to see if I could find some pictures of one of one of these artifacts disassembled. The best example I found so far, that includes someone taking the cover off one of these things, is this Youtube video,This video also includes some video of the narrator hooking this thing up to his shower head, and trying to get some watts out of it. If you have not seen this video, it might be relevant to your original topic; i.e. "anyone have experience using these cheap hydro generators?"

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  • This kind of reminds me of Chris Hackett's ideas for post-apocalyptic coinage, as described in this video:

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  • Jack A Lopez commented on Shezi007's forum topic Making a power supply.2 months ago

    If you are trying to do what I think you are trying to do, the picture you have drawn is wrong. The wire you call "0 V" should be connected to a negative wire from one adapter, and a positive wire from the other adapter. I mean take the picture you drew, and switch the output wires from one of those adapters, and that will look better.When you stack voltage sources on top of each other, it is always plus to minus, the same way as is done with battery cells.I mention this because this is probably something you have seen before. You know, you've seen a toy, or something, that takes 4 AA batteries, and they are all wired in series, with the positive (+) terminal from one, connected to the negative terminal (-) of the next to give 4*1.5V = 6.0 volts, across the whole stack.AC ...

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    If you are trying to do what I think you are trying to do, the picture you have drawn is wrong. The wire you call "0 V" should be connected to a negative wire from one adapter, and a positive wire from the other adapter. I mean take the picture you drew, and switch the output wires from one of those adapters, and that will look better.When you stack voltage sources on top of each other, it is always plus to minus, the same way as is done with battery cells.I mention this because this is probably something you have seen before. You know, you've seen a toy, or something, that takes 4 AA batteries, and they are all wired in series, with the positive (+) terminal from one, connected to the negative terminal (-) of the next to give 4*1.5V = 6.0 volts, across the whole stack.AC adapters can often, but not always, be stacked in series, in the same manner as battery cells, for to give more voltage, or to give more than two voltage rails. The quality that determines if this is possible, or not, is whether or not the the AC adapter is isolated,https://en.wikipedia.org/wiki/Galvanic_isolationfrom the mains power. And almost always, AC adapters are made this way, so there is no actual conductive path connecting the output rails, on the DC side, to the AC mains rails, named "hot" and "neutral".One thing to watch out for is some AC adapters, particularly those with a plug with a "ground" conductor, sometimes they will connect the negative terminal of the DC side to the ground wire of the mains supply. For example, for the ubiquitous desktop computer power supply (eg. ATX), the ground (=0 volts) is connected to the metal case, and also the ground wire of the mains supply.To stack two desktop PSUs in series, it is necessary to disconnect the wire that connects to the ground of the wall plug, and also make sure the two metal cases to do touch each other.Also, I am naively assuming you want three output rails, with voltages, {+12 V, 0 V, -12 V}When you write "12v-0v-12v", it is confusing because I cannot tell if "-" is a word separator, like a space or a comma, or if "-" is a math symbol meaning "minus". I am guessing you want, {+12 V, 0 V, -12 V}, because you said it was for an amplifier, and often, but not always, amplifiers want a supply like that.To be clear, when you put your voltmeter's probes between the +12 V rail and the -12 V rail, the voltmeter will read the algebraic difference between these two numbers, i.e. Vdiff = +12 V - (-12 V) = 12 V + 12 V = 24 V.

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  • Have you ever taken apart an ultrasonic humidifier?https://en.wikipedia.org/wiki/Humidifier#Ultrasoni...I see these things all the time in thrift stores, at low prices. I think people buy them in the Winter, when indoor air is dry, and then throw them away, or give them away, in the Spring. I know the mist produced by this kind of humidifier is not smoke. It is fog, tiny water droplets, but it kind of looks like smoke.Also, in taking apart a machine of this kind, you will discover the fan that moves the mist, is not a hugely powerful fan. Often it is a fan so quiet, that you would not know it was there, except by discovering it there, by taking the machine apart.Said another way: it does not take a lot of power to move smoke, or mist.I am naively guessing any kind of small fan wou...

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    Have you ever taken apart an ultrasonic humidifier?https://en.wikipedia.org/wiki/Humidifier#Ultrasoni...I see these things all the time in thrift stores, at low prices. I think people buy them in the Winter, when indoor air is dry, and then throw them away, or give them away, in the Spring. I know the mist produced by this kind of humidifier is not smoke. It is fog, tiny water droplets, but it kind of looks like smoke.Also, in taking apart a machine of this kind, you will discover the fan that moves the mist, is not a hugely powerful fan. Often it is a fan so quiet, that you would not know it was there, except by discovering it there, by taking the machine apart.Said another way: it does not take a lot of power to move smoke, or mist.I am naively guessing any kind of small fan would work, and I would suggest trying one or more of those square, brush-less, DC powered fans, that can be found cheaply, in large numbers, in junked computer hardware.https://en.wikipedia.org/wiki/Computer_fanThe speed of this kind of motor can be varied by providing it with more, or less, voltage, to make it run slower or faster. The direction of this kind of fan cannot be changed. So to effect direction control with a fan of this kind, you would probably have to use two of them, and maybe some cleverly designed duct work.And as long as I am linking to Wikipedia, so much, I might as well link to the article titled "Fog machine"https://en.wikipedia.org/wiki/Fog_machineI am guessing this is the kind of smoke machine you want for your sculpture. Moreover, I am guessing you want hot (or warm) smoke. Cold mist, made from pure water, like from an ultrasonic humidifier, has a tendency to condense, and leave little water droplets everywhere.

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  • I claim the usual trick for varying the speed of a universal motor, is a circuit with a TRIAC, that only gets turned on for a fraction of each half-cycle of the AC waveform.Moreover, I claim that TRIAC circuit is the same circuit used in TRIAC based lamp dimmers, and it is possible to use a use a lamp dimmer to sort of "throttle" mains power to universal motor.I have actually tried this, using a lamp dimmer to control the speed of the motor in a "shop-vac" style vacuum cleaner, and also an electric kitchen mixer. By the way, these experiments I have done, were done with 120 VAC mains power, and a lamp dimmer and loads rated for the same.I am naively assuming that lamp dimmers made for 220 VAC, and rated for power greater than 710 watts, or however much power the l...

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    I claim the usual trick for varying the speed of a universal motor, is a circuit with a TRIAC, that only gets turned on for a fraction of each half-cycle of the AC waveform.Moreover, I claim that TRIAC circuit is the same circuit used in TRIAC based lamp dimmers, and it is possible to use a use a lamp dimmer to sort of "throttle" mains power to universal motor.I have actually tried this, using a lamp dimmer to control the speed of the motor in a "shop-vac" style vacuum cleaner, and also an electric kitchen mixer. By the way, these experiments I have done, were done with 120 VAC mains power, and a lamp dimmer and loads rated for the same.I am naively assuming that lamp dimmers made for 220 VAC, and rated for power greater than 710 watts, or however much power the load uses, can be found in India. The only thing that has me worried a little bit, is you say already tried something similar; i.e. "i tried it through electric fan regulator but it failed to vary the speed"However, I do not have a good mental picture of this "electric fan regulator", of what that is.Perhaps it is not the same thing as this TRIAC based lamp dimmer I am thinking of. If it is the same thing, well, obviously it would be dumb for me to recommend you try something you already tried.By the way, similar chatter on this topic can be found by asking your favorite search engine to tell you more about, "how variable speed drill works triac universal motor", https://duckduckgo.com/?q=how+variable+speed+drill...

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  • Single phase induction motor?I think those kind of motors kind of want to just run at one speed. If your motor was a universal motor, I would recommend just using one of those TRIAC based lamp dimmers. Those seem work well with the chopped up AC waveform that comes out of a lamp dimmer.So,uh, do you have any other electric motors? Like maybe an electric drill? A typical mains powered electric drill is a universal motor, plus a speed-reducing gear train, so the output shaft (the chuck) turns with less speed, and more torque, than the motor itself.A cordless drill might have comparable speed, and power. The interesting thing about cordless drills, is people often throw them away, or give them away, when the battery dies, which is almost inevitable. So these can be found on the used ...

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    Single phase induction motor?I think those kind of motors kind of want to just run at one speed. If your motor was a universal motor, I would recommend just using one of those TRIAC based lamp dimmers. Those seem work well with the chopped up AC waveform that comes out of a lamp dimmer.So,uh, do you have any other electric motors? Like maybe an electric drill? A typical mains powered electric drill is a universal motor, plus a speed-reducing gear train, so the output shaft (the chuck) turns with less speed, and more torque, than the motor itself.A cordless drill might have comparable speed, and power. The interesting thing about cordless drills, is people often throw them away, or give them away, when the battery dies, which is almost inevitable. So these can be found on the used market, like in thrift stores, for low prices. Or even cheaper if you find one in a dumpster! The challenge with with using a cordless drill, is that you will have to find a somewhat beefy DC power source for it, something that can really give it some amperes, the way its old battery used to, if you want to run it at full power.I have no idea what is this thing you call, "50' line on pulleys" Does that single-quote-mark (or apostrophe) mean "feet"? Like a clothes line? Like 50 feet in length?https://en.wikipedia.org/wiki/Clothes_line

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  • By the way, if you want kind of an overview of every known form of energy storage, with a table showing numbers for joules per kg (specific energy) and joules per liter (energy density), the Wikipedia article for "Energy density" has this.https://en.wikipedia.org/wiki/Energy_densityAlthough, many of the entries seen in these tables are a little too abstract to be useful, including entries like "anti-mater" and "ham sandwich"However, I noticed one of these, that is not a kind of battery, and like the water-in-a-tower idea, it is something purely mechanical. That is the entry for, "compressed air".The quote of 300 bar is kind of scary. That is a lot of pressure. A bar is about 15 PSI, and a typical garage, or construction type, air compressor has ...

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    By the way, if you want kind of an overview of every known form of energy storage, with a table showing numbers for joules per kg (specific energy) and joules per liter (energy density), the Wikipedia article for "Energy density" has this.https://en.wikipedia.org/wiki/Energy_densityAlthough, many of the entries seen in these tables are a little too abstract to be useful, including entries like "anti-mater" and "ham sandwich"However, I noticed one of these, that is not a kind of battery, and like the water-in-a-tower idea, it is something purely mechanical. That is the entry for, "compressed air".The quote of 300 bar is kind of scary. That is a lot of pressure. A bar is about 15 PSI, and a typical garage, or construction type, air compressor has a tank strong enough to withstand about 5 to 10 bar (or 75 to 150 PS.Just, intuitively, I am thinking the amount, and expense of plumbing required for a water tower, or compressed air tank, might be similar. Also there are plenty of existing power tools designed to run on compressed air directly.As a plus, even in places on Earth where water is scarce, atmospheric air is still plentiful.;-)

    I do not know these, "cheap hydro generators", to which you refer, but then I am not sure I have to.The principle of storing energy, by simply lifting mass against gravity, that principle is well known, and can be summarized in a single equation:U = m*g*hWhere U is stored energy (in joules), m is mass (in kilograms), g is the local acceleration due to gravity (typically 9.8 m*s^-2 ~=10m/s^-2, on Earth), and h is the height (in meters) through which the mass is lifted.Anyway, a few kilograms of water and a few meters of height, will give you a few 10s of joules of stored potential energy.In contrast, lithium-ion batteries can store kilojoules (i.e 1000s of joules) of energy, in cells that mass a few 10s of grams.The formula for energy stored in a battery is, approximately,U = ...

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    I do not know these, "cheap hydro generators", to which you refer, but then I am not sure I have to.The principle of storing energy, by simply lifting mass against gravity, that principle is well known, and can be summarized in a single equation:U = m*g*hWhere U is stored energy (in joules), m is mass (in kilograms), g is the local acceleration due to gravity (typically 9.8 m*s^-2 ~=10m/s^-2, on Earth), and h is the height (in meters) through which the mass is lifted.Anyway, a few kilograms of water and a few meters of height, will give you a few 10s of joules of stored potential energy.In contrast, lithium-ion batteries can store kilojoules (i.e 1000s of joules) of energy, in cells that mass a few 10s of grams.The formula for energy stored in a battery is, approximately,U = V*Q = integral(V*I*dt)where, again U is stored energy (in joules), and V is the battery's voltage (in volts), and Q is current capacity, which is roughly the time integral of current( Q=integral(I*dt)).Usually battery manufacturers put their current capacity quotes in units like mA*h (milliampere*hours) or A*h (ampere*hours), however if I want to get an estimate of for a battery's stored energy in joules, I have to convert that number to ampere*seconds, to get the units to work out correctly,i.e. (1 joule) = (1 volt)*(1 ampere)*(1 second) = (1 watt)*(1 second)As an example, consider the 18650 size Li-ion cell. I've got one here on my desk. I think I pulled it out of a broken laptop battery. It is a common size. The same sized cell, can be found in batteries for other consumer toys, like cordless drills, and maybe other things. This cell is cylindrical, like 19 mm in diameter, and 65 mm long. According to the Wikipedia page, "List of battery sizes", the current capacity for this cell is 1500-3600 mA*h.https://en.wikipedia.org/wiki/List_of_battery_size...The mass of this cell is about 45 grams, and that number is the number I got from putting one of these cells on a scale (balance), and weighing (massing) it.Just as sort of a guestimate, I am going to take the typical cell voltage, of 3.7 volts, and multiply that by 1500 mA*h = 1.5 A*h, the lower number on that range given in the table.(3.7V)*(1.5A*h) = 5.55 W*h = (5.55J/s)*(3600s) = 20000 J = 20 kJNext I am going to ask, how many kilograms of water, lifted to a height of 1 meter (or 10 meters) is needed to store the same amount of energy, that is 20 kilojoules.Well, first I'll consider a 1 meter high tower. U = m*g*h. Solve for m.m = U/(g*h) = ((20000J)/((10/m^s-2)*(1 m)) = 2000 kg.or about 2 metric tons of water (which takes up 2.0 m^3 volume), for a 1 meter high tower.Proportionally less water is needed for proportionally higher tower. In other words, if I build a tower 10 times as high, I only need to use 1/10 the mass; i.e.m = U/(g*h) = ((20000J)/((10/m^s-2)*(10 m)) = 200 kg.By the way, this simple calculation ignores losses due to inefficiency in the pump that does work to lift the water, or in the what you call "hydro generator" that receives work from falling water.If both of those were only 70% efficient. The efficiency of both combined would be about 0.7*0.7 = 0.49 ~= 50%, meaning the actual amount of water I need to store, would be roughly twice that for the ideal case.So what is the specific energy density for water stored in the 10 m tower?20 kJ/ 200 kg = 0.1 kJ/kgThe specific energy of Li-ion batteries, from the sidebar on the Wikipedia page for "Lithium-ion battery", is 0.36-0.875 MJ/kg = 360-875 kJ/kg.The ratio between those two is what? Like 3600 to 8750? So 1 kg of Li-ion batteries stores the same energy as 3600 to 8750 kg of mass on a 10 meter tower? Something like that.But, you know, you should check this math yourself. I've been known to make mistakes on this back-of-an-envelope type stuff.https://en.wikipedia.org/wiki/Back-of-the-envelope...

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  • I do not know why your experiment did not work.Although it seems like there has to be an easier way to make homemade hydrochloric acid, if that is the goal here.Starting with hypochlorite ion, ClO-, seems like trouble, because I think the chlorine atom in that is in a +1 oxidation state, and you want to reduce that to -1, i.e. chloride.https://en.wikipedia.org/wiki/HypochloriteI think the usual, textbook recipe for hydrochloric acid, starts with a chloride salt, typically sodium chloride, plus a strong acid, like sulfuric acid.NaCl + H2SO4 = NaHSO4 + HClI copied that reaction from the Wikipedia article for "Hydrogen chloride",https://en.wikipedia.org/wiki/Hydrogen_chlorideWould the same reaction work with a weak acid,like acetic acid, in household vinegar?NaCl +CH3COOH = NaCH3...

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    I do not know why your experiment did not work.Although it seems like there has to be an easier way to make homemade hydrochloric acid, if that is the goal here.Starting with hypochlorite ion, ClO-, seems like trouble, because I think the chlorine atom in that is in a +1 oxidation state, and you want to reduce that to -1, i.e. chloride.https://en.wikipedia.org/wiki/HypochloriteI think the usual, textbook recipe for hydrochloric acid, starts with a chloride salt, typically sodium chloride, plus a strong acid, like sulfuric acid.NaCl + H2SO4 = NaHSO4 + HClI copied that reaction from the Wikipedia article for "Hydrogen chloride",https://en.wikipedia.org/wiki/Hydrogen_chlorideWould the same reaction work with a weak acid,like acetic acid, in household vinegar?NaCl +CH3COOH = NaCH3COO + HCl I dunno. Using electrolysis to make chlorine gas from aqueous NaCl, that is pretty easy, although at the beginning of your post you maybe said you wanted to avoid Cl2 gas. By the way, HCl is pretty nasty in gaseous form too, and I think some of these reactions (like NaCl + H2S04) will tend to produce it that way. Also I think aqueous HCl spontaneously releases HCl gas, like it spontaneously "boils out", but the rate at which it does so, depends on temperature, and concentration of the aqueous HCl.In fact, I recall seeing, as a Youtube video, a method for purifying hydrochloric acid, and that method was just to put a container of aqueous HCl, and a container of pure water, next to each other, in a closed container big enough to hold both of them. This magic is made possible by gaseous HCl moving through the air, at room temperature.That video should not be too hard to find. I think it was this one.

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  • I must admit: My reply yesterday was not very constructive.The potential uses for a thing follow from its properties. The properties of your aluminum bottle are: lightweight, aluminum, pointy-shaped, vaguely cylindrical, resealable bottle, covered with garish beer logo advertising...I don't make any promises about the quality of the following ideas. You know, art is subjective.The properties, lightweight and pointy-shaped, suggest that you could attach a bunch of these to a swim cap, or baseball cap, so the tops of the bottles are all radiating outward with your head at the center. I have seen similar headdress worn by that guy, Jamiroquai, and whatshername, that big statue of the girl with the book and the torch, in New York's harbor.The fact that your aluminum bottles have cylindri...

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    I must admit: My reply yesterday was not very constructive.The potential uses for a thing follow from its properties. The properties of your aluminum bottle are: lightweight, aluminum, pointy-shaped, vaguely cylindrical, resealable bottle, covered with garish beer logo advertising...I don't make any promises about the quality of the following ideas. You know, art is subjective.The properties, lightweight and pointy-shaped, suggest that you could attach a bunch of these to a swim cap, or baseball cap, so the tops of the bottles are all radiating outward with your head at the center. I have seen similar headdress worn by that guy, Jamiroquai, and whatshername, that big statue of the girl with the book and the torch, in New York's harbor.The fact that your aluminum bottles have cylindrical symmetry suggests maybe you could make a chess pieces out of them. Perhaps two styles of beer, with different colored bottles, could serve as the two different colors of the opposing,16 piece, armies. I am guessing that some significant reshaping, using metal shears, hacksaw, etc, will be required to make them look, convincingly, like pawns, bishops, rooks, king, queen... The knights are probably going to be the hardest, since they're the only pieces that lack radial symmetry.I dunno. Salt and pepper shakers? That's kind of the same thing as the chess set, but much less arduous, since you only have to make 2 pieces instead of 32.Maybe you could make them into juggling pins. The shape, narrow on one end, wide on the other, is vaguely suggestive of this. Of course they do not weigh enough, but maybe if they were filled with something they would have better rotational inertial.Since their shape is round and smooth, maybe they have good aerodynamics. Perhaps they could be weaponized. Like, filled with concrete to make them heavy, easier to throw, or maybe filled with flammable liquid, like, an aluminum Molotov cocktail...https://en.wikipedia.org/wiki/Molotov_cocktailThe fact this container is resealable, that is maybe good from a weapons perspective too. https://en.wikipedia.org/wiki/Dry_ice_bombWhile on the topic of mad science, the fact that these bottles are electrically conductive, round, smooth, without sharp edges, suggests they might work well for storing electric charge. Like maybe this shape would work well for the rods, collectors, etc, in a dirod machine.https://duckduckgo.com/?q=dirod+electrostatic+gene...

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  • I am seriously wondering why you are interested in this particular container.Aluminum beverage containers are already more likely to be recylced, than containers made from other materials. I mean, aluminum cans have been recycled for ages. The reason for this is because making aluminum from bauxite ore, is energy intensive, particularly intensive in its use of electricity, which costs more than other forms of energy, like for example raw coal.As sort of a contrast, for making steel, raw coal can serve as both heat source (for melting the metal) and reducing agent (for reducing metal oxides to metal). But coal is not a powerful enough reducing agent to reduce aluminum from its oxides. Aluminum is one of those metals with high reduction potential, so pretty much the only economic way t...

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    I am seriously wondering why you are interested in this particular container.Aluminum beverage containers are already more likely to be recylced, than containers made from other materials. I mean, aluminum cans have been recycled for ages. The reason for this is because making aluminum from bauxite ore, is energy intensive, particularly intensive in its use of electricity, which costs more than other forms of energy, like for example raw coal.As sort of a contrast, for making steel, raw coal can serve as both heat source (for melting the metal) and reducing agent (for reducing metal oxides to metal). But coal is not a powerful enough reducing agent to reduce aluminum from its oxides. Aluminum is one of those metals with high reduction potential, so pretty much the only economic way to make it from its oxides, is some kind of electrolytic process. Raw coal is cheaper than raw electricity, like by the kilojoule, and I think this is most of the reason for the cost difference of new (or scrap) steel versus aluminum, like price per kilogram.That's kind of a long story, I guess, but my main point here is that aluminum containers have been recycled for ages, like even before recycling was fashionable. The Wikipedia article on "Aluminium recyling", I think has some numbers that back up the story I'm telling.https://en.wikipedia.org/wiki/Aluminium_recycling"Recycling scrap aluminium requires only 5% of the energy used to make new aluminium.[1] For this reason, approximately 31% of all aluminium produced in the United States comes from recycled scrap.[2] Used beverage containers are the largest component of processed aluminum scrap, and most of it is manufactured back into aluminium cans.[3]"Moreover, this new screw top design, is, I think, more likely to get re-used, or upcycled since it is a better container, because it is resealable. I mean the fact that it is resealable increases the number of possible ways it could be upcyled.So basically, I get that you are interested in this container, and you think it has great potential for being upcycled into something brilliant.However I think the motivation for doing something with one, or more, of these screw top cans... I think the motivation is going to have to come from the utility of the created thing itself, rather than from a desire to merely, "to keep these out of landfills."The reason why, is this can's basic design, aluminum with screw top cap, is already keeping it out of landfills.It just seems to me that your call to action, for you know: Hey, everybody, lets make something great out of a aluminum screw top cans! It would be more moving if you could explain, like, why this particular container has such great upcycle potential, instead of merely admonishing us to, keep 'em out of teh landfills.

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  • I was not the first person to notice this. Credit for that goes to this comment:https://www.instructables.com/community/Unable-to-...Anyway, I am glad I was able to help in some small way, and I thank you for fixing it.

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  • Jack A Lopez commented on gclark0812's forum topic Help with charging capacitors 2 months ago

    Well, the cheap and dirty way to do this is by using a voltage multiplier, https://en.wikipedia.org/wiki/Voltage_multiplierlike a doubler, or a tripler.By the way, the Wiki article for "Rectifier" is, I think, kind of a prerequisite. https://en.wikipedia.org/wiki/RectifierI mean, understanding simple rectifier circuits, like half wave and full wave, this is maybe a prerequisite for understanding the more complicated voltage multiplier circuit.Keep in mind, the peak voltage of the AC waveform is greater than its RMS value by a factor of 1.4142 (=square-root of 2). For example a sinusoidal AC voltage with 120 volts RMS, has a peak value of around 170 volts, and it is the peak value that gets rectified, and charges the capacitors in these various rectifier circuits. Thus a tri...

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    Well, the cheap and dirty way to do this is by using a voltage multiplier, https://en.wikipedia.org/wiki/Voltage_multiplierlike a doubler, or a tripler.By the way, the Wiki article for "Rectifier" is, I think, kind of a prerequisite. https://en.wikipedia.org/wiki/RectifierI mean, understanding simple rectifier circuits, like half wave and full wave, this is maybe a prerequisite for understanding the more complicated voltage multiplier circuit.Keep in mind, the peak voltage of the AC waveform is greater than its RMS value by a factor of 1.4142 (=square-root of 2). For example a sinusoidal AC voltage with 120 volts RMS, has a peak value of around 170 volts, and it is the peak value that gets rectified, and charges the capacitors in these various rectifier circuits. Thus a tripler fed with 120 VAC could produce a DC voltage of around 3*170 = 510 VDCThis page,http://www.kronjaeger.com/hv/hv/src/mul/is all about voltage multipliers, and the reason I want to link to it is because it has a formula for calculating the impedance offered by a Villard cascade voltage multiplier, and that number will be meaningful, if you are wondering about how big or small the capacitors in your voltage multiplier should be, based on how fast (how much time it will take) for to charge your capacitor bank.Anyway, that is the cheap and dirty way. Cheap because the component count is low. Dirty because it does not offer much in the way of isolation,https://en.wikipedia.org/wiki/Galvanic_isolation from the AC mains.Perhaps a better way might be to build an inverter, to make your 100s of volts AC, from low voltage DC. Then rectify that AC into DC to give you your 450 volts DC. There are maybe a few advantages to doing things this way. The first is because you can make the frequency faster, the capacitors in a subsequent multiplier stage, or filter stage, can be much smaller. Also if your capacitor charger is DC powered, then maybe you can run it on batteries, and make your machine portable. You know, that way your ultimate terror weapon, or whatever this thing is, does not need an extension cord. ;-PFinal note: I don't know if you knew this or not, but many recipes out there for homemade capacitor chargers, use a camera flash charger, because these are cheap, easy to find. This page,http://www.talkingelectronics.com/projects/XenonFl...does a good job of explaining how these camera flash charger circuits work, it could maybe serve as inspiration, if you want to build a battery powered capacitor charger.

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  • Jack A Lopez commented on Tman179's forum topic DC motor regulation2 months ago

    The input DC voltage to the motor is only part of the problem.The angular speed (rpms) at which the motor turns, also depends strongly on mechanical loading. By that I mean, the resistance torque being offered by whatever you have the motor connected to, it is going to slow the shaft speed, independent of whatever voltage is being placed across the motor.A better way to build a shaft that turns at constant angular speed, is to use a sensor, to measure the shaft's angular speed, and then use signal from the sensor to drive a feedback loop.I.e. if the sensor says the speed is a little bit below the target, then give the motor a little more juice (meaning voltage, or time-averaged voltage if using PWM). Conversely, if the sensor says speed is a little above the target value, then give the ...

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    The input DC voltage to the motor is only part of the problem.The angular speed (rpms) at which the motor turns, also depends strongly on mechanical loading. By that I mean, the resistance torque being offered by whatever you have the motor connected to, it is going to slow the shaft speed, independent of whatever voltage is being placed across the motor.A better way to build a shaft that turns at constant angular speed, is to use a sensor, to measure the shaft's angular speed, and then use signal from the sensor to drive a feedback loop.I.e. if the sensor says the speed is a little bit below the target, then give the motor a little more juice (meaning voltage, or time-averaged voltage if using PWM). Conversely, if the sensor says speed is a little above the target value, then give the motor a little less juice.By the way, I have actually built the thing I am describing. I never got around to writing it up as an instructable, but I upped some pictures of it, to a discussion on the Answers forum, here.https://www.instructables.com/community/Not-sure-w...That was about two years ago, I guess. Had to use a search engine to remember where I put that comment.Do a Ctrl-F, and look for the word "SG3524", the particular PWM IC I used, if you want to quickly jump to the comment I wrote.I don't dare ask if anyone wants an instructable on that topic (how to build a phonograph from an old cordless drill), but I am kind of wondering:Is there enough detail in that brief comment, for you to understand what I built there, like how it works? Does what I wrote there make sense?

    Well, it depends on what the mechanical load is. If the load offers a mostly constant resistance torque, then a motor supplied with a constant voltage (or constant time averaged voltage if using PWM) will give mostly constant speed.Including a big heavy flywheel, with lots of rotational inertia, can help smooth out small disturbances that otherwise cause the speed to change, momentary slow down, or momentary speed up, for a system with little rotational inertia.Actually, on the subject of phonograph turntables, I have not taken one apart recently, but I think the last time I did, I noticed the mechanism driving the turntable included a big heavy flywheel. So there probably something to this idea of including a flywheel.On the subject of "speed control", a lot of electric ma...

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    Well, it depends on what the mechanical load is. If the load offers a mostly constant resistance torque, then a motor supplied with a constant voltage (or constant time averaged voltage if using PWM) will give mostly constant speed.Including a big heavy flywheel, with lots of rotational inertia, can help smooth out small disturbances that otherwise cause the speed to change, momentary slow down, or momentary speed up, for a system with little rotational inertia.Actually, on the subject of phonograph turntables, I have not taken one apart recently, but I think the last time I did, I noticed the mechanism driving the turntable included a big heavy flywheel. So there probably something to this idea of including a flywheel.On the subject of "speed control", a lot of electric machines, in particular power tools, that call themselves "variable speed", are not using a closed-loop speed regulator, like I described previously. They are just using a kind of voltage regulator. Well usually it is PWM, which is essentially regulated, time-averaged, voltage. And that kind of control (open-loop control) is good enough for a cordless drill. Actually, I probably should have mentioned this first, but your topic included the word "regulation", and you asked will a constant voltage keep a motor, and a gearbox ( and I don't know what else) turning at constant speed.I think I maybe explained the most complicated way first, but the reason why I thought to explain it this way is because you were asking for a regulator. In my mind, a regulator is necessarily a closed-loop kind of control; i.e. a speed regulator will necessarily have a speed sensor, and feedback from this.Regarding this jargon of open-loop control versus closed-loop control, if you do not already grok the difference between these, the first section of the Wikipedia article titled, "Control system", explains the difference between open-loop and closed loop, https://en.wikipedia.org/wiki/Control_system#Open-...using an example of a building's heating system with a boiler controlled by a timer. It's on some of the time, off some of the time. Essentially this is the same thing as PWM, and it is open-loop.The closed-loop is what you get when you introduce a temperature sensor, and use feedback from that sensor to decide when the boiler turns on, and when it turns off, also called a, "thermostat".The wiki article for "Control system" might lead you to other places too. For example there are purely mechanical speed regulators, like that "centrifugal governor" in the first picture, and I think those are as just as complicated as electronic regulators, but maybe the mechanical version will be more meaningful to someone, "not inclined on circuitry".

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  • Jack A Lopez commented on eramsell's forum topic Chips in smoke detectors2 months ago

    Um, are these from ionization type smoke detectors?Do they still have the chamber with the tiny Am-241 alpha source? I mean, that is the truly interesting part.See:https://en.wikipedia.org/wiki/David_HahnPerhaps you already know this.Regarding the IC, I think usually there is just one of them, and if you can look at the data sheet for Motorola's MC14467,http://www.alldatasheet.com/datasheet-pdf/pdf/1125...I think this IC is a typical example. There is some kind of really high impedance comparator, like with FET inputs or something, for to sense a DC voltage on the ionization-chamber thing. Also there is an alarm sound circuit, capable of driving a piezo speaker at earsplitting volume. And that is pretty much it.So, I am guessing an old smoke detector board could be re-purposed as an...

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    Um, are these from ionization type smoke detectors?Do they still have the chamber with the tiny Am-241 alpha source? I mean, that is the truly interesting part.See:https://en.wikipedia.org/wiki/David_HahnPerhaps you already know this.Regarding the IC, I think usually there is just one of them, and if you can look at the data sheet for Motorola's MC14467,http://www.alldatasheet.com/datasheet-pdf/pdf/1125...I think this IC is a typical example. There is some kind of really high impedance comparator, like with FET inputs or something, for to sense a DC voltage on the ionization-chamber thing. Also there is an alarm sound circuit, capable of driving a piezo speaker at earsplitting volume. And that is pretty much it.So, I am guessing an old smoke detector board could be re-purposed as an alarm, or annoying noise maker, but I am not sure what else it, a board without the ionization chamber, could be used for.Regarding the numbers you mentioned, {8506, 8605, 8502}, I do not recognise these, but that does not mean the data sheets for your ICs are not out there somewhere.Smoke detector IC is kind of niche thing anyway. I am expecting the total number of smoke detector ICs out there to be small, so maybe try just asking alldatasheet, or some other IC data site, to show you ICs with "smoke detector" in the description.http://category.alldatasheet.com/index.jsp?Searchw...This is kind of shotgun approach, but one of the ICs that shows up in that result might be similar, or the same, to the ones you have.

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  • Hey. Thanks for the reply, and thanks for pointing out the previous bug report. If I had noticed the previous report, I would have just gone there to post, "Me too."

    So that means it's safe to say(write) the words, "hot glue gun" out loud?How about "0.44 caliber glue sticks"? Can I say that? I swear, that's the size ammo my hot glue gun (HGG) takes. Well, the documentation did include the word, "caliber", but it said 0.44 inches diameter, and I think that is actually the same thing.https://en.wikipedia.org/wiki/CaliberWell, I'm glad it, the bug, is not that we can't talk(write) about guns here.Anyway, I sent unto Super_Me, a PM including most of what I tried to write in my "answer". I also politely informed him (I'm guessing he's a him) about how his Answers topic broke the instructables web site. Ha!;-)

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  • I have also noticed my comments to this question disappear.Also I wrote a topic, in bugs, about this, here,https://www.instructables.com/community/comments-t...I am considering moving what I wrote there, over to this topic, for the sake of putting all of this particular discussion in one place.

    Yeah. Here is what I wrote for that topic:Several times over the past few days, I have tried to reply to a particular question on the Answers forum, specifically the question linked here: https://www.instructables.com/answers/Any-decent-good-hot-glue-guns-for-beginners/ I write a comment in the little editor-box-thing. Then when I click the "Make comment" button, and the text of the comment I just wrote disappears. Voop! It's gone! Then my disappeared comment does not become posted to this topic. Where did the text I just wrote go to? Did it go somewhere? Or is really and truly gone from this universe? That is assuming I did not save a copy of it to a clipboard, or text editor first. Yeah. Big mystery, right? I kind of suspect there is something wrong wit...

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    Yeah. Here is what I wrote for that topic:Several times over the past few days, I have tried to reply to a particular question on the Answers forum, specifically the question linked here: https://www.instructables.com/answers/Any-decent-good-hot-glue-guns-for-beginners/ I write a comment in the little editor-box-thing. Then when I click the "Make comment" button, and the text of the comment I just wrote disappears. Voop! It's gone! Then my disappeared comment does not become posted to this topic. Where did the text I just wrote go to? Did it go somewhere? Or is really and truly gone from this universe? That is assuming I did not save a copy of it to a clipboard, or text editor first. Yeah. Big mystery, right? I kind of suspect there is something wrong with just this particular topic: https://www.instructables.com/answers/Any-decent-good-hot-glue-guns-for-beginners/ Just ask yourself why an easy question like this, is somehow 4 days old, with zero answers (and zero comments total) so far. Is no one, besides me, trying to comment on, or answer, this easy question? Please feel free to try to post a comment there yourself, just to see what happens. Possibly the topic is activating your filters, because it has a bad word in it: Three letters. Starts with "g". I have heard rumors you all are running some crazy filters to try to protect users here from reading bad words, and perhaps from writing bad words too! Also because you always strongly suspect the problem is with my computer (and maybe it is) I must tell you the browser I am trying to do this with is: Firefox 51.0.1 (32-bit) and that is Mozilla Firefox for Ubuntu. and, uh, it looks like I am running it under: Ubuntu 12.04 (precise) I thank you for your attention to this matter, and I applaud your efforts to make Instructables less buggy.

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  • Jack A Lopez commented on Not_Tasha's instructable Putting Together a FibreShare Box3 months ago
    Putting Together a FibreShare Box

    Wow! I had no idea there were so many people making handmade yarn.Well, I guess I do not truly know how many people spin handmade yard. However, this 'ible provides evidence of there being at least two: you, and the recipient of your gift, who actually asked for "raw fleece", and "locks", and stuff. Wow! That is so weird!Baa baa black sheep, have you any wool?https://en.wikipedia.org/wiki/Baa,_Baa,_Black_Shee...;-)The existence of fibreshare.org strongly suggests there are more of these people out there. Maybe a whole subculture?It's a shame they misspelled the word "fiber" in their domain name. I truly hope they're not losing the people trying to find them via fibershare.org.Or maybe the bad spelling is intentional. Perhaps "fibre" is the old t...

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    Wow! I had no idea there were so many people making handmade yarn.Well, I guess I do not truly know how many people spin handmade yard. However, this 'ible provides evidence of there being at least two: you, and the recipient of your gift, who actually asked for "raw fleece", and "locks", and stuff. Wow! That is so weird!Baa baa black sheep, have you any wool?https://en.wikipedia.org/wiki/Baa,_Baa,_Black_Shee...;-)The existence of fibreshare.org strongly suggests there are more of these people out there. Maybe a whole subculture?It's a shame they misspelled the word "fiber" in their domain name. I truly hope they're not losing the people trying to find them via fibershare.org.Or maybe the bad spelling is intentional. Perhaps "fibre" is the old timey spelling of "fiber", and they wanted their domain name to have a kind of old timey vibe to it.I dunno. Subtleties like that are mostly lost, totally unappreciated, by literal-minded persons like myself.https://www.merriam-webster.com/dictionary/literal...Which reminds me: the only other, like, modern human, I can think of who spun (and dyed) his own yarn or twine, from raw fibers, was Kevin Dunn, the author of a book titled, "Caveman Chemistry". There exist free versions of that book's chapters on spinning and dyeing, and I'm going to link to those here, for anyone reading this who wants to know more about that.http://cavemanchemistry.com/oldcave/projects/twine...http://cavemanchemistry.com/oldcave/projects/dye/i...Actually, wait! There was that one other guy too. This was a real, actual person I actually talked to, briefly, in real life, at an Earth Day event, a few years back. He was making twine from plant fibers, something from the Yucca genus,https://en.wikipedia.org/wiki/YuccaMoreover, he claimed to be using the same traditional methods as the natives of this land, who did this from time immemorial.Just to be jerk, I asked him if the ancients used plastic clothespins, like he did, to keep his work from unraveling when he had to set it down for a moment.He said the ancients did not use plastic clothespins, but they did not need to, because the ancients were not frequently interrupted by ignorant people asking dumb questions.;-P

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  • Jack A Lopez commented on iceng's forum topic Dentist radiation chart4 months ago

    Occasionally I see, or hear, these stories about how human health could be improved, if only there were an inexpensive way to make potassium, with just the stable isotopes, of mass 39 and 41. I guess it could be called, "depleted potassium", meaning depleted of the mass 40 isotope.The other day, when I was trying to answer the latest water-electrolysis question in the Answers forum, I was looking at some of Cody Reeder's Youtube videos(i.e. Cody's Lab Youtube channel), and one of the videos I noticed was him making some noises about, "depleted potassium", here,https://www.youtube.com/watch?v=NpHQ87RNQBc

    Yeah. Leap years. I guess they're a little longer than regular years.

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  • Jack A Lopez commented on iceng's forum topic Dentist radiation chart4 months ago

    You know, eating a single banana per day, for a year, exposes you to 365 times the radiation of eating a single banana.

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  • Jack A Lopez commented on Shezi007's forum topic Converting 1A to 5A4 months ago

    http://writingexplained.org/then-vs-than-differenc...

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  • That, rectifier that is switched from half-wave to full-wave, would be really easy for a mains powered tool, since mains power is AC, but I do not see how that works in a battery powered tool. Like, where does the AC come from?It seems to me, for a battery powered thing, a PWM circuit would be at least as cheap as making AC from DC, and then rectifying it.

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  • The usual way battery powered power tools implement speed control is by way of PWM (pulse width modulation), with a typical being a cordless drill.Essentially there is a circuit that can produce this PWM signal with a duty cycle (i.e. fraction of the time it is on) varies in proportion to the distance the trigger is pulled. For example, if the trigger is pulled 25% of the way in, it gives PWM on 25% of the time. If the trigger is pulled 67% it gives PWM on 67% of the time. Et cetera.Then that PWM signal drives a big fat transistor, often a MOSFET, for to switch voltage to the motor in time with the PWM signal, so the time averaged voltage seen at the motor is 25%, or 67%, or whatever percent, of the full battery voltage.So that kind of makes it clear why people replying to this thread...

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    The usual way battery powered power tools implement speed control is by way of PWM (pulse width modulation), with a typical being a cordless drill.Essentially there is a circuit that can produce this PWM signal with a duty cycle (i.e. fraction of the time it is on) varies in proportion to the distance the trigger is pulled. For example, if the trigger is pulled 25% of the way in, it gives PWM on 25% of the time. If the trigger is pulled 67% it gives PWM on 67% of the time. Et cetera.Then that PWM signal drives a big fat transistor, often a MOSFET, for to switch voltage to the motor in time with the PWM signal, so the time averaged voltage seen at the motor is 25%, or 67%, or whatever percent, of the full battery voltage.So that kind of makes it clear why people replying to this thread are suggesting you are suggesting you pull the guts out of a cordless drill, and use that.However, what I think those people are failing to consider, is the question of, "How does your leaf blower implement its existing speed control?"I know you said it was only two speeds, but is it making that happen by way of PWM plus big fat transistor? That is not an outrageous assumption. A lot of battery powered power tools use that method, but maybe for your thing, the designer decided not to make it proportional, but rather just two levels, selectable by a switch.I mean, it would be kind of a lucky break if most of the PWM stuff was already there, in your leaf blower, and all you had to add was a potentiometer.Or that might be wishful thinking, for it to be that easy. In any case, the peoples who are telling you to use PWM, or the same kind of motor control found in a cordless drill, I think those peeps are on the right track.

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  • Preparation of a Shredder for Various Tests.

    I thank you for the link. This is helpful.

    By the way, I have been sort of watching a similar project, called "Precious Plastic", and I might as well share some links into that for anyone interested in what their shredder looks like.https://preciousplastic.com/en/videos/build/shredd...https://davehakkens.nl/community/forums/topic/wher...

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  • Preparation of a Shredder for Various Tests.

    Do you have a link to the page for the shredder you bought?When I search eBay for "shredder", all I can find is, "paper shredder" and "cheese shredder".

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  • Jack A Lopez commented on Jack A Lopez's instructable How to Listen to Light8 months ago
    How to Listen to Light

    Dang! That vdownload.eu link is broken, but I found the same video posted here, at metacafe.com,http://www.metacafe.com/watch/148666/rob_zombie_s_..."...because I thought, why let a good jackalope go to waste?"

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  • Jack A Lopez commented on mikeasaurus's instructable Beer Shooter9 months ago
    Beer Shooter

    OH MY GOD! DON'T DO IT!!! oh wait... I meant to say: Cheers!;-)I am impressed by your 3D design skills, and also your use of gun language puns, in the Intro step to this 'ible.

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  • Jack A Lopez commented on makedo-able's instructable Makedo Giant Windball10 months ago
    Makedo Giant Windball

    Sometimes it is nice to discover the academic name for a thing.For example, I think it was just a few months ago when I discovered this thing,https://www.instructables.com/id/Trammel-of-Archime...has a name other than "bullsh!t grinder".

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  • How to Lubricate a Lock Using Graphite From a Pencil

    That sounds like a good method. Thanks for commenting. I am glad to hear it worked.

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