More like from the 60's... :-) look: hpmuseum.net/display_item.php?hw=82 "The 9125A was the companion plotter for the 9100 calculator. This single-pen plotter connected to the I/O slot at the back of the 9100. The 9125A had a plotting surface of ten inches by 15 inches and employed *electrostatic paper hold down* "
I think there would not happen that much, as the power of charge adhesion will decrease with distance squared. The paper is within a few milimeters when it is pulled to the whiteboard, the user will be at least 40-50 centimeters away, so we're talking about at least 1/1000th or even less of the force to the hairs.
Dave, stop apologizing about the new lab! You just moved over man. We all know it's going to take a few months for harmony to set back in. We're here for you and the content, the rest is just adder. It'll get done when it gets done. Looks great anyway! Thank you for your efforts and great content!
TH-cam creators should mind less about there camera, mic, lightning etc. As long as there is no annoying things going on I dont notice any difference. For some youtubers that bought expensive gear I actually thought it decreased their quality.
@@gamingSlasher Yes yes yes!!! I have noticed that as well!! At times filming in 60fps actually does the same. You gain this sharpness that wasn't there before and actually detracts from the video. Not saying this one but I have noticed it with some other creators and wondered if its due to the scene or lighting that makes it more pronounced. This video and his indoor shots benefit from 60fps due to the content, I think at least. Either way I do agree that a lot of the fussing about that creators feel is necessary, really isn't. Other than audio....bad audio (unclear or low) is a major detractor but Daves audio is usually always great! He has such a distinct voice as well that if the audio was bad, we would really notice it. Either way, his vid's are always stellar, even when he is fussing about nonstop about it because he thinks is shit. lol. Its the perfectionist in him I think; and its his full time job so he wants to always be better.
Unfortunately with the glare from the clear plastic sheet, it doesn't look as good on camera as a regular whiteboard. Especially what you wrote with the green marker is hard to see.
is this the kind of thing we've seen in TV shows et al for decades ... where blueprints / xray films / etc are stuck up on an illuminated wall and Important People nearby immediately notice some invariably-plot-thickening detail?
Hi Dave, physics graduate here! I just wanted to address some things: every dielectric inserted into a capacitor will feel an attractive force that is directly proportional to the relative dielectric constant of the material as well as the potential between the plates of the capacitor. I strongly feel that this is the principle of operation of this witheboard! This behavior is simply a consequence to the fact that every system tries is best to minimise it's energy. Even though this could seem a little counterintutive: the system is exerting a force upon the dielectric to minimise his energy?! An in-depth explanation is not something that can be written in a youtube comment but I hope that it sparkled some interest to do some research on your own. This is a classic example in electromagnetism and more in depth descriptions and calculations can be found all over the internet. For those who are interested, there's a chapter in the Feynman lectures on physics which is pretty clear (as with all Faynmans lectures), and are available for free on the site of Caltech university www.feynmanlectures.caltech.edu/II_10.html
Exactly. But there is some paradox. When we insert an object into a capacitor the capacitance increases and energy stored in the capacitor (assuming constant voltage source) increases. If energy in the direction of movement increases it should give repulsive force, although.
@@pamersiel When you increase the permittivity (which adding an object on the surface does), you decrease the voltage, so with the same charge, the energy drops. Voltage is *not* constant when attaching an object. The external voltage from the power supply is mostly irrelevant for this, the supply is too low-power to keep up the voltage when attaching an object. The easiest way to think about permittivity is the "ease" of an electric field moving through it. Adding a high-permittivity object to the system is equivalent to reducing the distance between charges, which reduces potential energy.
I'm guessing this causes polarization of the molecules on the attached medium, as in opposite charges attract to each "plate" underneath the whiteboard. Since there are approximately equal area on each "plate", charge balance is maintained in the paper so it's pretty low-energy to polarize.
I dunno, saying coloumbic force like that sounds a lot like colonic force. That's a rather shitty force. Ok, I'll show myself out for the low quality joke.
I think the word that you were looking for is "permeate" (of the electric field). That's a pretty interesting / clever device. I am guessing that it's working by creating a bunch of dipoles in the material that you stick on the surface, which bridge the gaps. Since the electric field will sort of spread out in arcs from the edges of the two plates, it will permeate what ever object you place on it. Since every object has a dielectric constant, the permeated electric field will induce a dipole which is proportional to k*E, where k is the constant and E is the electric field. And then the distribution of charge created from the induced dipoles attract the medium to the surface, with a stronger local electric field. That also explains why paper and aluminium foil were sticking better than wax paper, having a dielectric constant of 3.5, 10.8, and 2.5, respectively. This is compared to the dielectric constant in air which is nearly 1. It's also interesting that one of the gap pairs have an increased surface area (the wiggles) when compared to the other. That might have something to do charge distribution, and / or making sure that the reverse dipoles are smaller (since each gap will induce a dipole in the direction of the electric field). Note that the above is just a guess, especially since it's been a while since I have taken an E&M course.
@@EEVblog The gap sizes are the same, but the shape / geometry of them is not. Notice how the first one wiggles / meanders, which increases the overall length of the gap (so lets say that one is + to - going upward). Then the next gap is completely straight (the shortest possible gap length - lets say that is - to + going upward). Then the pattern repeats (so every - to + gap has more surface area in proximity to the object placed on the surface, as opposed to the + to - gap, potentially leading to stronger - to + dipoles). Note that this is in comparison to just repeating the wiggle / meandering gap for each transition between the two plates. Edit: The point to the different geometries is that the effect is on a differential area dA (probably something like gap width * the line element of the gap path, ds), where the larger the surface, the larger the overall integral, and thus the larger the effect.
The rows alternate in "polarity" of the peaks and troughs, but that's the only difference. The starting edge meanders differently to facilitate that phase difference. Apart form that they are identical across the board.
@@EEVblog At 8:51 for example, there are 4 rows on the left side of the screen, which alternate in polarity. So all of the rows with the peaks and troughs above them, are of the same polarity. And the alternate rows all have the peaks and troughs below them, so there is a preference to where the peaks and troughs are placed. I can't think of a better way to describe what I am trying to say without actually drawing a diagram. It also occurred to me, that the geometry of the gap may have been entirely to just conserve space (i.e. they would have made peaks and troughs for all of the gaps, but that would have meant smaller charge plates, or spacing them further apart). Either way, I just thought it was interesting that there appeared to be a preference in how the plate gaps were laid out.
@@EEVblog I think the meandering is to make sure you get positives and negatives across anything you lay down on it. If it was a straight edge then small pieces rectangular pieces of paper might not cross a positive-negative pair so won't get much of an induced dipole and so it won't stick. There's also what I think hjups is trying to say which is the meander means you more efficiently get induced dipoles crammed into the area of a sheet so it sticks better. You could really dense straight fingers but I guess that's less efficient since you just get alternating is dipoles in one direction rather than spots of dipoles in 2D which might also help the edges of sheets stick on and not peel off.
currently working on two electrostatic blackboards for an Australian institution. One of the HV generators (black box) is faulty and typically theres no information on either leaving me pondering , how many volts on the secondary? I can source HV geneators however, how many Kv? So my question to the collective, what is a typical secondary voltage on an electrostatic board? (board size is approx 1.5m x 2m)
4:30 As one who likes proper units for checking: k_sub_e == 8.9875×10⁹ N·m²/(A·s)² Cheers! Edited to add: discovered on Wikipedia that the SI value of the constant is exactly 8987551787.3681764 N·m²/(A·s)².
Interesting info. I took a 8.5x11 sheet of paper and put alternate strips of old alarm window foil (.4" wide or so) on it spaced .15" or so apart and hooked it up to my flyback driver (on a variac), set it to 1 or 2 kv and it works! Attracts wood or paper. Curiously, it doesnt seem to attract plastic of any kind! Tried printer transparencies, plastic bread bags, even Mouser shipping pouches dont work.... that was unexpected... I was under the impression that it worked on about anything when I came across this tech in 2014.
All these had *electrostatic paper hold down* : The 7200A (1969) hpmuseum.net/display_item.php?hw=83 , the 9862A (1972) www.hpmuseum.net/display_item.php?hw=78 , and the 7210A (1972) hpmuseum.net/display_item.php?hw=69
Hey take your AL Foil and your parchment paper, build some capacitors. Use a roll of AL Foil and a roll of Saran Wrap for dielectric. Bob's Not Anybody's Uncle.
Oh cool present!!! Does this has any double meaning message requesting more fundamentals Fridays... 😄 Great videos Dave!! I’m looking forward to continue learning so interesting stuff with your next video using that board 😉 Lots of thanks Dave !!
10:40 That's 3000 hours, just over 4 months, so 9 months if you switch it off during the night. Which nobody is going to remember. Why doesn't it switch off automatically when the magnets holding the transparent layer are connected to the board? All it takes is a reed switch. You only need the charge when the top layer is removed.
its also used as an "electrostatic chuck" for holding wafers prior to ion implantation in semiconductor manufacture.....very cool Applied Materials use them
How nice to get videos relating to electrostatic stuff, after searching for information about a old (~70s?) electrostatic “air cleaner” that I bought after stumbling upon it on a second hand place. It’s a bit scary with the thought of high voltages in the box, but it does give that nice ozone fresh air smell too… ;)
A whiteboard? How about one of those newfangled presentation screens? (touch-sensitive LCD with built-in PC that can run presentations or an application that mimics a whiteboard. you can put images on the screen, write on top of it, and save the result)
How aren't you getting a violent static discharge stinging your finger? Is it something to do with the board being non-conductive so the charge can not quickly get to the contact point to be discharged like it does with a car? A car gets charged to 2-3kV usually at which point it inflicts quite a sting even through the acrilic varnish...
Nice, could you maybe do a bit more of a backward engineering schematic thing with these kind of videos? That way it gives a bit more information than just screwing things open
@@EEVblog . Yes i know. But that's different than an actual circuit. Of course the principles are the same obviously but it's interesting to see how manufacturers implemented it.
Merlin Gallagher - The difference would be pretty trivial, not worth a reverse engineering effort that would take longer than this entire video took to shoot edit and upload.
I watched both videos (Cockcroft-Walton and microcontroller multiplier) and still don't quite understand how this works to get such high voltages (2-3 kV). The board has only 8 caps and 9 diodes, so i guess it is a 4 stage multiplier which gives 5 times the input voltage. That would need at least 400V to start with. How do they generate that from the max. 6V battery? Just switching this tiny inductor? Or am i missing something obvious?
The name of that board, is my last name. I was listening in the background, and it freaked me out when you said the name. I though I had finally lost my mind and my iPad had started talking to me. LOL :-)
When it comes to transferring electric fields I just say that a material channels the field, instead of conducts the field. It seems more pedantically pleasing.
hi dave , maybe you can do a video on DaveCad too.. i see some trial editions popping up on various youtube channels. where can we get the full version ? greetz ;)
The Roland dxy penploters had these static holder function on for the a2 en up format so the static charge to hold paper is a very old way to hold paper :) just some information , ,😁
I think that the terminology was good, I would say that the new configuration with the paper “as a dielectric” is a lower energy state of the system, so it takes work to separate the paper - into the higher energy state.
Dave, how did you get such a thick neck? Are you in wrestling training? Hmm, this looks kinda cool. If you had a PCB thru-hole template, you could sketch away with components.
If it produces a significant force with big pieces of paper, shouldn't it produce a perceivable amount of force on your hand/arm? I'd be fascinated to hear what sort of sensation that produces.
@EEVblog: I'm not so much interested in how you could deploy a whiteboard or how well your lighting situation in your lab is. That's nothing it takes an engineer for really. ;-) What about the fact that (and how) the PIC could survife in such an environment, or will it suffer at some timepoint in the future from electrostatic damage, like the Philips controlpanel-/ remotecontrol processors in old philips tube TV's that went nuts and showed all kind of chinese characters on the screen but did no longer work? That controllers were positioned directly under the picture tube where you of course have (more or less well shielded) from the graphite outside of the display tube the acceleration voltages of about 16-20 kV's.
I wonder if the voltage potential could've been measured with a known high value resistor in series with a multimeter, or with a calibrated surface area conductive plate, measuring the thickness of the board surface, and hanging a weight to see when it falls off (board facing down to avoid calculating friction).
cool!.. that'll make things nice and easy.. it needs electrostatic repulsion mode to get the hairs off it tho! dont worry about the quality Dave..it looked fine...much cleaner than my shitty vids!
If you are looking for interesting ways to do tutorials with drawings you might look into light boards. There are several videos on the technique. The only downside is you probably do not want to wear a shirt with text on it because it will be appear backwards when you mirror the video get what you are writing to show in the correct direction.
How I would describe the working principle of this thing is that it produces an electric field in the air in front of it. The field flows out from the positively charged electrode and into the negatively charged one, basically forming a capacitor with the board surface and air as it's dielectric. The electric field is mostly tangential to the surface. When an insulator is added in front of the board, charges in it will be polarised, creating an electrostatic force holding it to the board. On the other hand when you placed the foil on the board, electric influence will be the main factor affecting the situation, effectively moving charges in the foil to exactly mirror the charges in the board, again pushing it into the board. This also explains why the voltage drops when the foil is placed on the board; the foil increases the capacitance of the board significantly by effectively reducing the distance between the electrodes by creating two capacitors connected in series.
when I saw the title I had a totally different idea of what this thing was going to be. I imagined a whiteboard that charged up, you drew on with some special marker then when you wanted to erase it you pressed a button that grounded the board or reversed the polarity and all the particles from the marker fell off and left it blank :D
9:35! Yes the current does go "through" the plates/object - as per your video about current "through" a capacitor! I dont know really - i just remembered your capacitor vid discussion... edit: oh wrote too soon - you mention it...
HP used to use electrostatic hold for their desktop plotters. You'd drop in a piece of graph paper, push the hold button, et voila, the paper clamped down to the bed.
Anything to do with the video EEVblog #748 - How Do Transistors Work? on how the the electrons are attracted through the holes to allow the flow through the gate?
So... how many circuits will you kill with this thing around? :)
Dave is going to wear his wireless ESD wristband. Everything will be fine. ;)
ALL of the .o3 cent and .o1 cent Padauk devices!!!
Old plotters (like the HP 7044A I did a teardown a while ago) use electrostatic to hold down paper on the plotter surface. It was from the 80's...
Wacom made a digitizer tablet with electrostatic to hold the paper. Worked quite well.
@n0ckter 18.5'x17.5'x5.5' pretty heavy (~30lbs), 7047A is around 53lbs.
More like from the 60's... :-) look: hpmuseum.net/display_item.php?hw=82 "The 9125A was the companion plotter for the 9100 calculator. This single-pen plotter connected to the I/O slot at the back of the 9100. The 9125A had a plotting surface of ten inches by 15 inches and employed *electrostatic paper hold down* "
I remember using an A3 HP pen plotter around 1999 which had an electrostatic paper hold. Nothing new in this product.
I still have an electrostatic A4 sized HP plotter. It's not 55lb. Although I don't know what 1lb weighs like.
This is terribly racist against blackboards. Your attitude is problematic.
Imagine: What would happen if someone with long hair stand in front of it....
Imgert Berg they would explode
I think there would not happen that much, as the power of charge adhesion will decrease with distance squared. The paper is within a few milimeters when it is pulled to the whiteboard, the user will be at least 40-50 centimeters away, so we're talking about at least 1/1000th or even less of the force to the hairs.
@@Slartibartfas042 but if their hair got drawn into it and made contact, then there could be a reasonable amount of force behind it.
Dave, stop apologizing about the new lab! You just moved over man. We all know it's going to take a few months for harmony to set back in. We're here for you and the content, the rest is just adder. It'll get done when it gets done. Looks great anyway!
Thank you for your efforts and great content!
TH-cam creators should mind less about there camera, mic, lightning etc. As long as there is no annoying things going on I dont notice any difference. For some youtubers that bought expensive gear I actually thought it decreased their quality.
@@gamingSlasher Yes yes yes!!! I have noticed that as well!! At times filming in 60fps actually does the same. You gain this sharpness that wasn't there before and actually detracts from the video. Not saying this one but I have noticed it with some other creators and wondered if its due to the scene or lighting that makes it more pronounced. This video and his indoor shots benefit from 60fps due to the content, I think at least. Either way I do agree that a lot of the fussing about that creators feel is necessary, really isn't. Other than audio....bad audio (unclear or low) is a major detractor but Daves audio is usually always great! He has such a distinct voice as well that if the audio was bad, we would really notice it. Either way, his vid's are always stellar, even when he is fussing about nonstop about it because he thinks is shit. lol. Its the perfectionist in him I think; and its his full time job so he wants to always be better.
I'm not sure he is apologising or just quoting Doc Brown from Back to the future... ;-)
Unfortunately with the glare from the clear plastic sheet, it doesn't look as good on camera as a regular whiteboard. Especially what you wrote with the green marker is hard to see.
Cool idea! Might want to keep it well away from static sensitive parts tho
Interesting. If it gets us more tutorials then great!
Ah but what would you like to see?
Personally I'd like to find out more about audio synthesizers waveform shaping.
;)
I'd be interested in that too ... I'm considering building some DIY synth modules :)
5:09 would it work with an antistatic bag?
yeh! show them inside out and oudside out! Interesting!
Dont do it. The universe will implode then.
It would
Just like with tinfoil.
ESD bags don't magically kill electrons, after all. They leak it out of the surface before it can build up.
Swap those multiplier caps out to quadruple the value.... MORE POWER!!!
is this the kind of thing we've seen in TV shows et al for decades ... where blueprints / xray films / etc are stuck up on an illuminated wall and Important People nearby immediately notice some invariably-plot-thickening detail?
Hi Dave, physics graduate here! I just wanted to address some things: every dielectric inserted into a capacitor will feel an attractive force that is directly proportional to the relative dielectric constant of the material as well as the potential between the plates of the capacitor. I strongly feel that this is the principle of operation of this witheboard! This behavior is simply a consequence to the fact that every system tries is best to minimise it's energy. Even though this could seem a little counterintutive: the system is exerting a force upon the dielectric to minimise his energy?! An in-depth explanation is not something that can be written in a youtube comment but I hope that it sparkled some interest to do some research on your own. This is a classic example in electromagnetism and more in depth descriptions and calculations can be found all over the internet. For those who are interested, there's a chapter in the Feynman lectures on physics which is pretty clear (as with all Faynmans lectures), and are available for free on the site of Caltech university www.feynmanlectures.caltech.edu/II_10.html
possibly
Exactly. But there is some paradox. When we insert an object into a capacitor the capacitance increases and energy stored in the capacitor (assuming constant voltage source) increases. If energy in the direction of movement increases it should give repulsive force, although.
@@pamersiel When you increase the permittivity (which adding an object on the surface does), you decrease the voltage, so with the same charge, the energy drops. Voltage is *not* constant when attaching an object.
The external voltage from the power supply is mostly irrelevant for this, the supply is too low-power to keep up the voltage when attaching an object.
The easiest way to think about permittivity is the "ease" of an electric field moving through it. Adding a high-permittivity object to the system is equivalent to reducing the distance between charges, which reduces potential energy.
I'm guessing this causes polarization of the molecules on the attached medium, as in opposite charges attract to each "plate" underneath the whiteboard. Since there are approximately equal area on each "plate", charge balance is maintained in the paper so it's pretty low-energy to polarize.
@@__dm__ That is exactly the same - permittivity = ability to be polarized
Now you just have to find a A0 plotter in the dumpster so you can print stuff to put on that.
I dunno, saying coloumbic force like that sounds a lot like colonic force. That's a rather shitty force.
Ok, I'll show myself out for the low quality joke.
Loving the AC/DC T-Shirt!
Did a quick search, nothing. Where can one get one from? As one wants one!
amorphia-apparel.com/grok/teslaedison-a-war-of-the-currents-ac-dc-mashup-shirt/#!/
Wiggle wiggle wiggle yeah! ha ha ha. Subtle :)
Argh. Now I want that t-shirt.
Wouldn’t want to have any static sensitive parts anywhere near that thing...
I think the word that you were looking for is "permeate" (of the electric field).
That's a pretty interesting / clever device. I am guessing that it's working by creating a bunch of dipoles in the material that you stick on the surface, which bridge the gaps. Since the electric field will sort of spread out in arcs from the edges of the two plates, it will permeate what ever object you place on it. Since every object has a dielectric constant, the permeated electric field will induce a dipole which is proportional to k*E, where k is the constant and E is the electric field. And then the distribution of charge created from the induced dipoles attract the medium to the surface, with a stronger local electric field. That also explains why paper and aluminium foil were sticking better than wax paper, having a dielectric constant of 3.5, 10.8, and 2.5, respectively. This is compared to the dielectric constant in air which is nearly 1.
It's also interesting that one of the gap pairs have an increased surface area (the wiggles) when compared to the other. That might have something to do charge distribution, and / or making sure that the reverse dipoles are smaller (since each gap will induce a dipole in the direction of the electric field).
Note that the above is just a guess, especially since it's been a while since I have taken an E&M course.
permeate sounds ok
All gaps seems the same size to me.
@@EEVblog The gap sizes are the same, but the shape / geometry of them is not. Notice how the first one wiggles / meanders, which increases the overall length of the gap (so lets say that one is + to - going upward). Then the next gap is completely straight (the shortest possible gap length - lets say that is - to + going upward). Then the pattern repeats (so every - to + gap has more surface area in proximity to the object placed on the surface, as opposed to the + to - gap, potentially leading to stronger - to + dipoles).
Note that this is in comparison to just repeating the wiggle / meandering gap for each transition between the two plates.
Edit: The point to the different geometries is that the effect is on a differential area dA (probably something like gap width * the line element of the gap path, ds), where the larger the surface, the larger the overall integral, and thus the larger the effect.
The rows alternate in "polarity" of the peaks and troughs, but that's the only difference. The starting edge meanders differently to facilitate that phase difference. Apart form that they are identical across the board.
@@EEVblog At 8:51 for example, there are 4 rows on the left side of the screen, which alternate in polarity. So all of the rows with the peaks and troughs above them, are of the same polarity. And the alternate rows all have the peaks and troughs below them, so there is a preference to where the peaks and troughs are placed. I can't think of a better way to describe what I am trying to say without actually drawing a diagram. It also occurred to me, that the geometry of the gap may have been entirely to just conserve space (i.e. they would have made peaks and troughs for all of the gaps, but that would have meant smaller charge plates, or spacing them further apart). Either way, I just thought it was interesting that there appeared to be a preference in how the plate gaps were laid out.
@@EEVblog I think the meandering is to make sure you get positives and negatives across anything you lay down on it. If it was a straight edge then small pieces rectangular pieces of paper might not cross a positive-negative pair so won't get much of an induced dipole and so it won't stick. There's also what I think hjups is trying to say which is the meander means you more efficiently get induced dipoles crammed into the area of a sheet so it sticks better.
You could really dense straight fingers but I guess that's less efficient since you just get alternating is dipoles in one direction rather than spots of dipoles in 2D which might also help the edges of sheets stick on and not peel off.
8:50 wiggle wiggle wiggle yeah! :D
Dave CAD 2.0!
Wiggle, wiggle, wiggle, wiggle, yeah!
if you double the distance the force drops four times (not by a quarter)
I never noticed the reduced sound or video quality.
Colors are off... you can see the auto white balance change at 5:34
What was the capacitance of the white board ? Was expecting an LCR meter wired up to measure the boards capacitance.
currently working on two electrostatic blackboards for an Australian institution. One of the HV generators (black box) is faulty and typically theres no information on either leaving me pondering , how many volts on the secondary? I can source HV geneators however, how many Kv? So my question to the collective, what is a typical secondary voltage on an electrostatic board? (board size is approx 1.5m x 2m)
4:30 As one who likes proper units for checking:
k_sub_e == 8.9875×10⁹ N·m²/(A·s)²
Cheers!
Edited to add: discovered on Wikipedia that the SI value of the constant is exactly 8987551787.3681764 N·m²/(A·s)².
Interesting info. I took a 8.5x11 sheet of paper and put alternate strips of old alarm window foil (.4" wide or so) on it spaced .15" or so apart and hooked it up to my flyback driver (on a variac), set it to 1 or 2 kv and it works! Attracts wood or paper. Curiously, it doesnt seem to attract plastic of any kind! Tried printer transparencies, plastic bread bags, even Mouser shipping pouches dont work.... that was unexpected... I was under the impression that it worked on about anything when I came across this tech in 2014.
All these had *electrostatic paper hold down* : The 7200A (1969) hpmuseum.net/display_item.php?hw=83 , the 9862A (1972) www.hpmuseum.net/display_item.php?hw=78 , and the 7210A (1972) hpmuseum.net/display_item.php?hw=69
Hey take your AL Foil and your parchment paper, build some capacitors. Use a roll of AL Foil and a roll of Saran Wrap for dielectric. Bob's Not Anybody's Uncle.
My vintage Roland DXY-1200 A3 Pen Plotter has this feature. See it in action here th-cam.com/video/1C1AJ5uGmJ0/w-d-xo.html
Oh cool present!!! Does this has any double meaning message requesting more fundamentals Fridays... 😄
Great videos Dave!!
I’m looking forward to continue learning so interesting stuff with your next video using that board 😉
Lots of thanks Dave !!
10:40 That's 3000 hours, just over 4 months, so 9 months if you switch it off during the night. Which nobody is going to remember. Why doesn't it switch off automatically when the magnets holding the transparent layer are connected to the board? All it takes is a reed switch. You only need the charge when the top layer is removed.
This will be DaveCAD2.0, you will be able to annotate photos of PCBs like in CliveCAD and I hope the quality will be as good as DiodeGoneWild'sCatCAD
its also used as an "electrostatic chuck" for holding wafers prior to ion implantation in semiconductor manufacture.....very cool Applied Materials use them
I can just imagine the state of Professor Martyn Poliakoff’s hair after a lecture using one! 🤔😂
How nice to get videos relating to electrostatic stuff, after searching for information about a old (~70s?) electrostatic “air cleaner” that I bought after stumbling upon it on a second hand place. It’s a bit scary with the thought of high voltages in the box, but it does give that nice ozone fresh air smell too… ;)
A whiteboard? How about one of those newfangled presentation screens?
(touch-sensitive LCD with built-in PC that can run presentations or an application that mimics a whiteboard. you can put images on the screen, write on top of it, and save the result)
I immediately thought "Hair!" when you said it's an electrostatic board. And you immediately mentioned them. ;)
How aren't you getting a violent static discharge stinging your finger? Is it something to do with the board being non-conductive so the charge can not quickly get to the contact point to be discharged like it does with a car? A car gets charged to 2-3kV usually at which point it inflicts quite a sting even through the acrilic varnish...
Nice, could you maybe do a bit more of a backward engineering schematic thing with these kind of videos?
That way it gives a bit more information than just screwing things open
I've done a whole video on Cockcroft Walton multipliers
th-cam.com/video/ep3D_LC2UzU/w-d-xo.html
@@EEVblog . Yes i know. But that's different than an actual circuit. Of course the principles are the same obviously but it's interesting to see how manufacturers implemented it.
Merlin Gallagher - The difference would be pretty trivial, not worth a reverse engineering effort that would take longer than this entire video took to shoot edit and upload.
I watched both videos (Cockcroft-Walton and microcontroller multiplier) and still don't quite understand how this works to get such high voltages (2-3 kV). The board has only 8 caps and 9 diodes, so i guess it is a 4 stage multiplier which gives 5 times the input voltage. That would need at least 400V to start with. How do they generate that from the max. 6V battery? Just switching this tiny inductor? Or am i missing something obvious?
The name of that board, is my last name. I was listening in the background, and it freaked me out when you said the name. I though I had finally lost my mind and my iPad had started talking to me. LOL :-)
haha like your T-shirt Tesla / Edison same as AC / DC :-)
When it comes to transferring electric fields I just say that a material channels the field, instead of conducts the field. It seems more pedantically pleasing.
hi dave , maybe you can do a video on DaveCad too.. i see some trial editions popping up on various youtube channels. where can we get the full version ? greetz ;)
a video for EEVblog th-cam.com/video/jxk0m2h3Vw0/w-d-xo.html it doesn't even know that it's an amplifier.
You could build an electro-static speaker from that! ..oh you said it!
The Roland dxy penploters had these static holder function on for the a2 en up format so the static charge to hold paper is a very old way to hold paper :) just some information , ,😁
Tearing down a new toy, potentially ruining it forever. The Canadian term for this is "pulling an AvE"
thanks for doing ADVERTICING
A video on Thanksgiving Day? Sorry, got to go eat some more turkey. :)
I think that the terminology was good, I would say that the new configuration with the paper “as a dielectric” is a lower energy state of the system, so it takes work to separate the paper - into the higher energy state.
I thought the video Q was great Dave. I'd be more than happy with the result!
I love the train running on the PCB track image. Can you share it please?
draw on the white board with the film lifted up, then lower the clear film and draw over your drawing !
How on earth is it possible to ramp up a few volts to kilovolts from those batteries?
Your Duracell's are expired.
Your Duracells, too.
You might be able to power it from a little photovoltaic panel and never have to change batteries.
is there a limit to how much stuff you can stick befor there is to much loss and stuff starts falling off
Dave, how did you get such a thick neck? Are you in wrestling training?
Hmm, this looks kinda cool. If you had a PCB thru-hole template, you could sketch away with components.
Must be the camera angle.
Get shocked giving a presentation, bonus.
If it produces a significant force with big pieces of paper, shouldn't it produce a perceivable amount of force on your hand/arm? I'd be fascinated to hear what sort of sensation that produces.
Will thrown slices of bologna stick to that board?
Coulomb-ian Force
@EEVblog: I'm not so much interested in how you could deploy a whiteboard or how well your lighting situation in your lab is. That's nothing it takes an engineer for really. ;-)
What about the fact that (and how) the PIC could survife in such an environment, or will it suffer at some timepoint in the future from electrostatic damage, like the Philips controlpanel-/ remotecontrol processors in old philips tube TV's that went nuts and showed all kind of chinese characters on the screen but did no longer work? That controllers were positioned directly under the picture tube where you of course have (more or less well shielded) from the graphite outside of the display tube the acceleration voltages of about 16-20 kV's.
...or just get a SMART board? I was one of the System Engineers for SMART for several years (before they moved all design to China)!
"Is that a word...? It is now."
How big could you go ? Interesting
I take it you don't have a 1000M high voltage DC probe.
Or an electrostatic voltmeter....
I wonder if the voltage potential could've been measured with a known high value resistor in series with a multimeter, or with a calibrated surface area conductive plate, measuring the thickness of the board surface, and hanging a weight to see when it falls off (board facing down to avoid calculating friction).
neat.
Let's see it in a week time, after it accumulated all the dust
What if you use neutronium-paper?
Was it a Cockcroft walton multiplyer + a boost converter?
Watch the video, it's linked in
Throw your LCR meter on that, and try a couple dielectrics on top of the board! If it's measurable.
We use a magnet...
cool!.. that'll make things nice and easy.. it needs electrostatic repulsion mode to get the hairs off it tho!
dont worry about the quality Dave..it looked fine...much cleaner than my shitty vids!
Silly, you don't have a train on a PCB, you have a BUS! :)
04:40 if you double the distance force will drop by quarter... Doesn't sound right? :/
Hold the phone. You do Tough Mudder?
can it attract and capture dust from the air?
Needs a DaveCAD logo!
If you are looking for interesting ways to do tutorials with drawings you might look into light boards. There are several videos on the technique. The only downside is you probably do not want to wear a shirt with text on it because it will be appear backwards when you mirror the video get what you are writing to show in the correct direction.
How I would describe the working principle of this thing is that it produces an electric field in the air in front of it. The field flows out from the positively charged electrode and into the negatively charged one, basically forming a capacitor with the board surface and air as it's dielectric. The electric field is mostly tangential to the surface. When an insulator is added in front of the board, charges in it will be polarised, creating an electrostatic force holding it to the board. On the other hand when you placed the foil on the board, electric influence will be the main factor affecting the situation, effectively moving charges in the foil to exactly mirror the charges in the board, again pushing it into the board. This also explains why the voltage drops when the foil is placed on the board; the foil increases the capacitance of the board significantly by effectively reducing the distance between the electrodes by creating two capacitors connected in series.
More like "cool ohms"
Dave cad got a hardware update :D
when I saw the title I had a totally different idea of what this thing was going to be. I imagined a whiteboard that charged up, you drew on with some special marker then when you wanted to erase it you pressed a button that grounded the board or reversed the polarity and all the particles from the marker fell off and left it blank :D
ALFoil = Alien Life Form oil
Imagine getting all hair sucked of your head and stuck to this whiteboard right when you insert last battery :DDD
DaveCAD 3.0
9:35! Yes the current does go "through" the plates/object - as per your video about current "through" a capacitor! I dont know really - i just remembered your capacitor vid discussion... edit: oh wrote too soon - you mention it...
Witchcraft!
This is cool.
Aka Circuit Murderer 2000.
Hey, could you use that surface to power a "Newton's Bells" demo?
You could have a box with all kinds of circuit symbols that take long to draw
May the force be with you.
HP used to use electrostatic hold for their desktop plotters. You'd drop in a piece of graph paper, push the hold button, et voila, the paper clamped down to the bed.
about the new lab: does it also have something like the goldmine that was the old dumpster or will that content go away?
Anything to do with the video EEVblog #748 - How Do Transistors Work? on how the the electrons are attracted through the holes to allow the flow through the gate?
Coulomb force: elementary weak force
Not that weak. The entire earth's gravity is pulling, fails to loose and loses from the Coulomb force.