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214CommentsAustin, TXJoined June 23rd, 2015
All project articles are being moved to www.netzener.net. I am no longer responding to emails from instructable.com. Eventually this account will be deleted. Please visit www.netzener.net for the latest projects and updates.

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  • netzener commented on DrewPaulDesigns's instructable Easy Tesla Coil!8 months ago
    Easy Tesla Coil!

    A nephew of mine came over to the shop one day and said, "Can you show me how to make a bird house? I want to make a bird house". I said, "Sure! I think I have some stuff that will work". We spend the rest of the day working on it and his dad put it up in his back yard. I used a plan recommended by a community of folks that knew a lot more about bluebird houses than I did. We went step-by-step. I described the materials we used, how the tools worked, taught him a little about shop safety practices (I admit it was mostly warnings not to touch this without me present), even told some exaggerated stories about birds during the tedious bits. With just a little instruction from me, he painted it himself and was very proud of the work. He held it up to his mother ...

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    A nephew of mine came over to the shop one day and said, "Can you show me how to make a bird house? I want to make a bird house". I said, "Sure! I think I have some stuff that will work". We spend the rest of the day working on it and his dad put it up in his back yard. I used a plan recommended by a community of folks that knew a lot more about bluebird houses than I did. We went step-by-step. I described the materials we used, how the tools worked, taught him a little about shop safety practices (I admit it was mostly warnings not to touch this without me present), even told some exaggerated stories about birds during the tedious bits. With just a little instruction from me, he painted it himself and was very proud of the work. He held it up to his mother and said, "Mom! I made a bird house. I made it!"I consider my nephew a Maker. And as a Maker myself, I got to show him how to do it in a safe place in a step-by-step way. We could have just bought a bird house from a store and painted it. It would have been much cheaper and easier. But building it together was a great way for us to connect socially and for me to share some of my experience.Sure he's a Millennial and I'm a "boomer". I didn't stab him or his parents in the back over it with claims my generation is superior to theirs. Or call his teachers up and yell at them for not teaching kids how to build a properly leaning birdhouse. Or blame people that don't share the same political views I do for my nephew not being able to think his way into building a bird house on his own.My nephew and I, we took full advantage of the knowledge someone else took the time to publish and we had a great experience together. I'm not embarrassed by that in the least. That's what Makers do. As a Maker, I've written no less than six Instructables since I joined this site in June 2015 to pay back this community for knowledge others have shared with me. And I'm just getting started. If someone takes that work and makes it their own and has a good time with it, I don't care how old they are or which country they are from, or whether they are conservative or liberal. But I'll commit to you this: be they expert or beginner, there will be enough information present to replicate the work and learn from it. That, in a larger context, is what Makers do.

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  • netzener commented on DrewPaulDesigns's instructable Easy Tesla Coil!8 months ago
    Easy Tesla Coil!

    That's actually a good point. I did search on ebay as you suggested, and although I didn't find the exact same parts I did find several that were pretty close (MJE3055 instead of TIP30C for example). But the coil does look very similar. At $19.50, the one I saw on ebay was a good deal.And I agree with you on the windings. The secondary coil is a resonant circuit using the winding inductance and inter-winding capacitance for L and C. So it doesn't have to be perfect. For appearance sake I personally would wind it as accurately as I could.I guess the best advice is that the buyer needs to look around, see whats available, and decide where the price is right. Because, yeah, there's a huge difference.

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  • Arduino Digital Clock With Alarm Function (custom PCB)

    With regard to the PCB, you and I are actually in full agreement. Your PCB quality is good because your layout work and attention to design rules were very good. I think you did a good job on the PCB.I can't say the same for nearly every other project I've seen from JLCPCB.But yours are good!

    I'm not a fan of EasyEDA or JLCPCB because many of the projects that end up on Instructables are junk. But I think this project is a bit better than it's peers. I like this one and think it looks totally cool. The author has included information on almost everything you would need to make the project including 3D print files for the case. So you don't really need to buy the PCB from JLCPCB. You could even wire this up on perfboard if you wanted to spend the time on it.For some reason EasyEDA doesn't produce clean schematics. Most of the projects using it have lines running through text or components, text too close, component outlines too small for the text within them... stuff like that. The schematic for this project has some of those, but it appears the author did spend a good...

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    I'm not a fan of EasyEDA or JLCPCB because many of the projects that end up on Instructables are junk. But I think this project is a bit better than it's peers. I like this one and think it looks totally cool. The author has included information on almost everything you would need to make the project including 3D print files for the case. So you don't really need to buy the PCB from JLCPCB. You could even wire this up on perfboard if you wanted to spend the time on it.For some reason EasyEDA doesn't produce clean schematics. Most of the projects using it have lines running through text or components, text too close, component outlines too small for the text within them... stuff like that. The schematic for this project has some of those, but it appears the author did spend a good bit of time getting the drawing to look right. I'm not sure if you can download the schematic from the EasyEDA site referenced by the author and use it with a better schematic editor, but at least there's a decent schematic to go with this project.I have the same issue with EasyEDA PCB layouts. Most projects featuring it look terrible. Wrong part outlines, extremely poor layout, silkscreen text run over pads, silkscreen text run over mounting holes, and worse... silkscreen text under component bodies. But the author of this project has taken the time to do a decent layout. All parts fit and are in their proper place. One of the few I've seen from JLCPCB that are even close to usable.The author includes a parts list, but I would have liked more complete specifications or a link on the Instructables site that shows where they can be ordered from. This is done in the authors EasyEDA site, so if you need more information on the parts you'll need to visit the EasyEDA site. It just would have been nice to see that on the Instructables site.A couple of omissions to be aware of:The push button switches aren't included in the parts list. You can see them in the picture but for the case to go together properly, the exact switch the author used needs to be ordered.The LCD display isn't specified. This might be one of those Arduino parts that everybody has and everybody knows what it is, but I think it would be better to include a description and link to the display used.The USB cable shown isn't specified. It would be great if a part number or link were provided for this.From an assembly standpoint:It's not clear how the LCD is wired into the main PCB. A little more information on that would be helpful for those who haven't done it before. Including this on a separate schematic page or illustration diagram would have been great. It's not clear what the USB cable with the bare leads is for. A little more information on that would be helpful. I'm assuming that cable is used to power the clock with 5V via connector CN1. But it's not clear and available documentation is silent.There is mention that a TTL to USB module is needed but that's not shown or described. A little more information on that module and how to connect it would be helpful for those who haven't programmed an Atmega chip in a dedicated PCB before. The less additional research the reader has to do, the more time they can spend just building the project.The video is nice to have, but half of it is the usual advertisement for JLCPCB. The author could have used that time to include additional information on how to build and program the project. But least every single step in this Instructable doesn't come with the usual appeal to "Buy the PCB! Buy the PCB!" I hate that.Minus a few missing parts, this is an project that can be made using the information the author has provided. It looks cool and you can build it however you want.

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  • How to Make Simple 4 Channel ON OFF Remote Control

    It is not possible to build this project using the information presented. It's just an advertisement for JLCPCB.The schematic is difficult to read. The parts list is incomplete. There are no schematic or PCB layout available. There is no assembly guide and no theory of operation.Just a few of the issues are:The relays are described in the parts as "12V 5 pole" (there is no such thing in that relay product line) but the relays used are single pole, double throw contacts.Note in the photos that there is a transistor with the center lead clipped off and a wire has been soldered to the heat sink pad. That was probably done because the PCB layout is wrong. The IR detector is pointing in toward the PCB instead of out toward the edge of the PCB. There is a resistor lead direct...

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    It is not possible to build this project using the information presented. It's just an advertisement for JLCPCB.The schematic is difficult to read. The parts list is incomplete. There are no schematic or PCB layout available. There is no assembly guide and no theory of operation.Just a few of the issues are:The relays are described in the parts as "12V 5 pole" (there is no such thing in that relay product line) but the relays used are single pole, double throw contacts.Note in the photos that there is a transistor with the center lead clipped off and a wire has been soldered to the heat sink pad. That was probably done because the PCB layout is wrong. The IR detector is pointing in toward the PCB instead of out toward the edge of the PCB. There is a resistor lead directly under the 7805 heat sink that can short the regulator output to ground. The relays were double throw yet no attempt was made to bring out anything but the NO contact. The parts list calls out a CR3032 but the batteries used in the photos is CR2032.I could go on. But as you can't actually order PCBs for this project, or make them yourself without redrawing the schematic and PCB layout, it's not necessary to critique further.

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  • Make 350W Power Inverter 12V 220V From OLD Computer Power Supply

    No, it's not my problem. It's your project so it's your problem. As the author, you bear the burden of accuracy and clarity for the reader. I'm simply pointing out that your schematics are incomprehensible. Your understanding of the circuits you are presenting isn't evident.I think your time would be better spent improving the quality of your technical illustration so your schematics make sense, learning some electronics theory so you can explain the circuits you present, and practice your PCB layout so the parts fit correctly and are in the proper location. It doesn't look like you know enough about what you are doing to present the project in way that someone else can follow along without a lot of confusion and wasted effort.And quite frankly, in this case it looks like you have r...

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    No, it's not my problem. It's your project so it's your problem. As the author, you bear the burden of accuracy and clarity for the reader. I'm simply pointing out that your schematics are incomprehensible. Your understanding of the circuits you are presenting isn't evident.I think your time would be better spent improving the quality of your technical illustration so your schematics make sense, learning some electronics theory so you can explain the circuits you present, and practice your PCB layout so the parts fit correctly and are in the proper location. It doesn't look like you know enough about what you are doing to present the project in way that someone else can follow along without a lot of confusion and wasted effort.And quite frankly, in this case it looks like you have reverse engineered a manufacturers product and are now trying to sell a PCB layout for it.It is not sufficient to specify the switching transformer in terms of, "Just get any switching transformer you find in any ATX power supply that just happens to be laying around". No. That will not work.You are even specifying a filter inductor in terms of, "just get any filter inductor you happen to find in an old power power supply". No. That will not work either.There are a lot more issues with this project. I could go on. But...Instead of addressing my comments, your public response is "go away". That speaks volumes to potential customers that your goal is not to educate, or even attempt to deliver a useful product. You are only in it for the money.

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  • DIY 240W Bench Power Supply Tutorials 0V to 24V 0 to 10A

    It was already clear from the articles you have posted on Instructables so far that you are not interested in showing anyone how to make something. You are only interested in promoting JLCPCB.I think your time would be better spent improving the quality of your technical illustration so your schematics make sense, learning some electronics theory so you can explain the circuits you present, and practice your PCB layout so the parts fit correctly and are in the proper location. It doesn't look like you know enough about what you are doing to present the project in way that someone else can follow along without a lot of confusion and wasted effort. For example:Specifying "A big heat sink" is in no way useful. A part number or supplier link would have been better.The converte...

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    It was already clear from the articles you have posted on Instructables so far that you are not interested in showing anyone how to make something. You are only interested in promoting JLCPCB.I think your time would be better spent improving the quality of your technical illustration so your schematics make sense, learning some electronics theory so you can explain the circuits you present, and practice your PCB layout so the parts fit correctly and are in the proper location. It doesn't look like you know enough about what you are doing to present the project in way that someone else can follow along without a lot of confusion and wasted effort. For example:Specifying "A big heat sink" is in no way useful. A part number or supplier link would have been better.The converter circuit absolutely depends on the inductor. But you haven't specified a part number or supplier link to obtain the inductor, and you haven't specified the core material, wire gauge, or number of turns if the reader is supposed to build the inductor themselves. Just specifying the inductance is not good enough.There are three potentiometers attached to the board, but haven't described what each does. So what is the builder supposed to do? Guess?Your BD140 driver transistor is right up against two 5W power resistors which I assume are the current sense element. At full output power those resistors will be dissipating over 7W. You probably don't want the driver transistor being heated by those resistors.With the exception of two components on your parts list, there are no tolerance, voltage rating, or dissipation ratings on any of the resistors and capacitors in your parts list. Specifying only the resistance value isn't sufficient.There are a lot more issues with this project. I could go on. But...Instead of addressing my previous comments, your public response is "go away". That speaks volumes to potential customers that your goal is not to educate, or even attempt to deliver a useful product. You are only in it for the money.

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  • netzener commented on educ8s's instructable ESP32 E-Paper Thermometer8 months ago
    ESP32 E-Paper Thermometer

    This is a very nice tutorial on the e-paper displays. I hadn't considered an e-paper display before but you are correct that the advantages are really good for ultra-low power information displays. LCD displays get so much attention I had forgotten about e-paper. The example project you chose is also a great one since it doesn't require rapid display updates which is perfect for e-paper, plus you get to work with a temperature sensor. So it's really two learning objectives in one. I like and I think it's very good work.

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  • Dynamic LED Lighting Shadow Box and Frame for Art:

    You've described this project very well with excellent attention to detail. Plenty of great assembly photographs and a good list of parts.From the video, I can't tell what the project does for the example artwork. I review the video on the light controller and I have the same issue. I can't tell that there is a significant difference in the presentation of the artwork using reflected light from within a frame. If there were some better before/after photographic examples or a video clearly showing the different lighting effects the frame and controller can produce, then I could get it. You did a lot of great work describing the project but the example video doesn't show off the results of that work.NetZener

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  • netzener commented on DrewPaulDesigns's instructable Easy Tesla Coil!8 months ago
    Easy Tesla Coil!

    There is certainly a lot of "spam" articles on this site. Mostly from people associated with JLCPCB in the Technology category.But I think Drew is sincere. He's just left a few things out which would help readers replicate the project without buying a kit. If you read the comments section on any of my projects, you'll see that occasionally I miss a thing or two and have to make corrections. But that just makes the project better. Making addition and corrections to this article will also help folks that buy the kit. The the kit web site has no assembly instructions. Instructables is the only source for information on how to build the project.There are a lot of Tesla coil projects on this site. Most of them are high school science projects that contain a lot of errors a...

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    There is certainly a lot of "spam" articles on this site. Mostly from people associated with JLCPCB in the Technology category.But I think Drew is sincere. He's just left a few things out which would help readers replicate the project without buying a kit. If you read the comments section on any of my projects, you'll see that occasionally I miss a thing or two and have to make corrections. But that just makes the project better. Making addition and corrections to this article will also help folks that buy the kit. The the kit web site has no assembly instructions. Instructables is the only source for information on how to build the project.There are a lot of Tesla coil projects on this site. Most of them are high school science projects that contain a lot of errors and omissions. These are young people learning physics and trying to figure things out. We've all been there. Drew is at a different level, however, which is why I think maybe he was running low on time and couldn't polish the article to a professional shine.What I was really concerned about was the cost of the kit. Drew presents himself as both artist and alternative energy activist. If someone wants a professional like Drew to wind a coil for them by hand (very tedious) to a very high aesthetic standard (which is very hard), then $200 is the price and delivery is 4 to 6 weeks. No argument from me.But the web site you order the kit from doesn't say that the buyer will receive a pre-wound coil. It shows a picture of one already wound. But the kit description says the buyer will receive a spool of magnet wire. Much of the hardware in the photos along with the transparent base and top are missing from the parts list as well. If I make the assumption that only what is written under "The kit includes the following" is all that is promised for delivery, I wouldn't consider the kit good value.I was hoping that Drew would clear that up which is why I spent the time to write a comment about it.NetZener

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  • netzener commented on DrewPaulDesigns's instructable Easy Tesla Coil!8 months ago
    Easy Tesla Coil!

    I can understand that you are offering a kit of parts to make building the project more convenient, but for those that would like to provide their own materials it would be nice if your parts list was more complete. After all, this site is called Instructables and the intent is to show readers how to make something. The information provided isn't complete enough for someone to replicate your work without buying what you're selling.The wire gauge and estimated length for the secondary coil isn't provided.The estimated length of wire needed for the secondary coil isn't provided.The voltage rating of the .1uF disk capacitors isn't specified. Why not use a single 0.33uF capacitor?The heat sink used isn't specified along with the fasteners used.The threaded rod used isn't specified along ...

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    I can understand that you are offering a kit of parts to make building the project more convenient, but for those that would like to provide their own materials it would be nice if your parts list was more complete. After all, this site is called Instructables and the intent is to show readers how to make something. The information provided isn't complete enough for someone to replicate your work without buying what you're selling.The wire gauge and estimated length for the secondary coil isn't provided.The estimated length of wire needed for the secondary coil isn't provided.The voltage rating of the .1uF disk capacitors isn't specified. Why not use a single 0.33uF capacitor?The heat sink used isn't specified along with the fasteners used.The threaded rod used isn't specified along with the nuts, washers, and plastic caps.The plexiglass top and bottom plates aren't specified.The 1K resistor power dissipation or tolerance value isn't specified.The current rating of the 12V power supply isn't specified.The above also isn't covered on the your web site. So I'm not sure what a customer would actually get if they ordered a kit. The Instructable mentions "pre-wound coils" but the web site doesn't. It says you get a roll of magnet wire. So it's not clear whether the buyer has to roll their own secondary or not. Certainly it looks like the primary coil has to be wound because the web site just shows a pile of #16 wire.I estimate you have maybe $25 to $35 in parts for this project, but your web site is asking for $200 plus shipping which frankly I think is unreasonable.I think this is an attractive project, but it needed more attention to detail. Especially if offering a kit for sale. I wouldn't purchase a kit based on the information provided on the web site.NetZener

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  • Electromechanical Decimal to Binary to Hexadecimal Converter

    Ah. I was afraid of that. The output port over-voltage suppression specification on the MC33996 was too optimistic or intended for the occasional spike, not a continuous stream of them.I'm guessing the AlfaZeta specification is very conservative given that they end up being used in outdoor environments. Makes sense.Thanks for the reply!NetZener

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  • netzener commented on mikeasaurus's instructable QR Coasters8 months ago
    QR Coasters

    Brilliant! Probably the best use of a 3D printer I've seen. And I am not a fan of 3D printing. These probably do not take a long time to print and they look great. Excellent idea.NetZener

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  • Make 350W Power Inverter 12V 220V From OLD Computer Power Supply

    The usual incomplete and incomprehensible project promoting junk circuits and PCBs from JLCPCB. This is nothing more than an advertisement. No one can reproduce this project with the information provided here. Based on the results I see on Instructables, no one should consider JLCPCB for any PCB work.

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  • Bass, Treble, and Volume USB Controller With Keyboard LEDs

    It took me moment reading through the source code to figure out what this project does. It wasn't obvious from the description. Then after reading deeper it is a "wired remote" for the frequency controls in the sound card you have. Do I have that right?I like the perfboard construction and the nice schematic you created. You did some nice wiring and the case looks really nice. A little more "theory of operation" would have helped me lock on to what the project was about a bit more quickly than I did. I was thinking, "Oooo. Digital filtering on Arduino". Off on a tangent. But I got back on the right page.NetZener

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  • How to Make High Power Led Dimmer+Dc Motor Speed Controller

    Don't waste your time on this. It's nothing more than an a PCB vendor promotion. No schematic, no theory of operation, incomplete parts list. It is not possible to replicate the project with the information provided. This is yet another junk circuit from JLCPCB.

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  • DIY 240W Bench Power Supply Tutorials 0V to 24V 0 to 10A

    This looks like nothing more than an advertisement for a PCB manufacturer. The schematic diagram is almost incomprehensible. You haven't indicated the inductor core type and number of turns, the parts list is inaccurate an incomplete, the VI meter isn't specified, and the power supply isn't clearly shown or specified.I'd like to be constructive by frankly it looks like the only reason this project exists is to promote a PCB vendor. There is no way anyone can replicate this project with the information provided.NetZener

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  • netzener commented on rachesv99's instructable Wireless Mouse Rechargable Mod8 months ago
    Wireless Mouse Rechargable Mod

    Connect a USB cable where? The connector shown on the outside of the mouse is a barrel connector.NetZener

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  • Brake Failure Indicator Using 555 Timer | DIY | Step by Step | How to

    I'm assuming that this circuit application is completely hypothetical.The primary braking system on all vehicles currently in use today is hydraulically actuated, not cable actuated. The primary brake is a direct mechanical link from the driver brake pedal to the brake master cylinder which is a vacuum assisted hydraulic control valve. There are no cables involved in this system what-so-ever.In cars with front hydraulic brakes only, the parking brake or "emergency brake" is cable actuated to the rear brake drums. This braking system is not the primary brake system for the vehicle when in motion. No one pulls the level to slow down their car as described in this article. It is only used when the vehicle in parked.The parking brake handle and associated cable assembly is fi...

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    I'm assuming that this circuit application is completely hypothetical.The primary braking system on all vehicles currently in use today is hydraulically actuated, not cable actuated. The primary brake is a direct mechanical link from the driver brake pedal to the brake master cylinder which is a vacuum assisted hydraulic control valve. There are no cables involved in this system what-so-ever.In cars with front hydraulic brakes only, the parking brake or "emergency brake" is cable actuated to the rear brake drums. This braking system is not the primary brake system for the vehicle when in motion. No one pulls the level to slow down their car as described in this article. It is only used when the vehicle in parked.The parking brake handle and associated cable assembly is firmly connected to the chassis, which is at electrical ground potential. The cable runs from the brake handle to the rear brake drums which may or may not be at ground potential depending on the suspension components used.For the circuit you describe to function, the user would need to install a wire from the brake cable at each rear brake drum to your circuit and detect when the cable is disconnected from the vehicle chassis ground. However your cable sensor must be connected to +12V in order to function. It is technically impossible for that cable connection to occur on any vehicle in use today.You did not describe or illustrate how this circuit should be attached to an automotive brake cable. So I have no way to explanation for how this circuit can actually function.Were you serious? Or just hypothetically describing a scenario for which this circuit apply?Because this circuit as described makes no sense at all.NetZener

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  • Electromechanical Decimal to Binary to Hexadecimal Converter

    Wow, I'm surprised nobody has commented on this article because it's actually pretty good. The author takes an electro-mechanical display technology typically found only in professional outdoor equipment and is figuring out how to put it to good use in something cool for indoor use. Like a clock. Well done!To benefit from your experience, I have a few questions/comments:I suspect you are using relays instead of h-bridge ICs to preserve the electro-mechanical style of the display and you like the clicky-ness?The AlfaZeta datasheet for the displays used in the project seem to recommend a minimum pulse width of 1ms at 19V for any segment, not to exceed 45ms during a 945ms period (5% duty cycle) in order to prevent heat accumulation in the energizing coils. Is that your experience with ...

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    Wow, I'm surprised nobody has commented on this article because it's actually pretty good. The author takes an electro-mechanical display technology typically found only in professional outdoor equipment and is figuring out how to put it to good use in something cool for indoor use. Like a clock. Well done!To benefit from your experience, I have a few questions/comments:I suspect you are using relays instead of h-bridge ICs to preserve the electro-mechanical style of the display and you like the clicky-ness?The AlfaZeta datasheet for the displays used in the project seem to recommend a minimum pulse width of 1ms at 19V for any segment, not to exceed 45ms during a 945ms period (5% duty cycle) in order to prevent heat accumulation in the energizing coils. Is that your experience with these displays?The AlfaZeta datasheet also suggests a minimum coil voltage of 16V. But the schematic for the project indicates you are using 12V. An reason for the difference or did you determine from experiment that 12V was sufficient?Are the 1.5KE18CA ESD suppressors and 1N5817 rectifiers really needed? The MC33996 has internal over voltage protection on each output specifically for inductive loads.You mentioned in the video that you were glad you didn't go for the full project on the first go. What issues did you find in the smaller project that made starting with it a better idea?Thanks for an interesting article. Made me think!NetZener

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  • netzener commented on kamil47's instructable Programmable Power Supply 42V 6A8 months ago
    Programmable Power Supply 42V 6A

    It's a nice looking project and you did a great job on it. It takes a lot of time to document a project like this as well as you have.A while ago I used the same approach you presented for a switch-mode variable power supply. The project in the image below is a dual supply 0-20V 0-2A so not on the same scale as the one you built but similar in concept. I use mine all the time for general analog and digital design. I like it because I made it, but it's also much smaller and lighter than an equivalent transformer-fed linear supply. For anyone reading through the article on Kamil47's power supply, the design does work quite well and his use of a programmable final converter is a nice touch. Don't settle for mangling an old ATX supply and attaching an LM317. Give this project a try a...

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    It's a nice looking project and you did a great job on it. It takes a lot of time to document a project like this as well as you have.A while ago I used the same approach you presented for a switch-mode variable power supply. The project in the image below is a dual supply 0-20V 0-2A so not on the same scale as the one you built but similar in concept. I use mine all the time for general analog and digital design. I like it because I made it, but it's also much smaller and lighter than an equivalent transformer-fed linear supply. For anyone reading through the article on Kamil47's power supply, the design does work quite well and his use of a programmable final converter is a nice touch. Don't settle for mangling an old ATX supply and attaching an LM317. Give this project a try and press the "I Made It" button.NetZener

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  • netzener commented on kamil47's instructable Programmable Power Supply 42V 6A8 months ago
    Programmable Power Supply 42V 6A

    This is a good single output variable power supply project and it will work. Series connecting the 24V supplies is an acceptable method for increasing the input voltage to the final DC-DC converter. As you mentioned, 24V supplies are available in greater power and size packages than are 48V supplies so using two 24V supplies is a good compromise.I only have a few comments:A 24V fan could be driven by one of the 24V supplies eliminating the small 12V converter. The fan control circuit would need to be redesigned. The control presented here is quick and simple but with just a little more work could be better.The 24V switching supplies have input fuse protection but the small 12V converter for the fan does not appear to be input fused. You might want to consider adding a small inline ...

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    This is a good single output variable power supply project and it will work. Series connecting the 24V supplies is an acceptable method for increasing the input voltage to the final DC-DC converter. As you mentioned, 24V supplies are available in greater power and size packages than are 48V supplies so using two 24V supplies is a good compromise.I only have a few comments:A 24V fan could be driven by one of the 24V supplies eliminating the small 12V converter. The fan control circuit would need to be redesigned. The control presented here is quick and simple but with just a little more work could be better.The 24V switching supplies have input fuse protection but the small 12V converter for the fan does not appear to be input fused. You might want to consider adding a small inline fuse at the 12V converter just to be safe.If you use different 24V supplies than specified by the author, be sure to verify with a multi-meter that the PCB mounting holes are electrically isolated from the DC outputs before you stack them together.The 24V supplies are specified as 100W converters which would make their maximum working output current approximately 4A. I'm not sure why Bangood is suggesting that they can operate at 5A unless that is a surge current rating. It's probably best to be conservative and call these 4A supplies.The 24V supplies are 120V/220V rated so if you live in the US, or another country with 120V AC you can use this power supply project with no problem. All you have to do is change the power cord to a NEMA 5-15P instead of the Europlug used by the author.I think the Ruideng 5005 with Communication is the better choice. The 5015 uses the large PCB board used in the first picture of the Instructable while the 5005 contains the display and converter in one piece. Much less space in the case and easier to build. And besides, the 24V supplies are only conservatively rated at 4A so there's no need for the larger 5015.I think the output power is overstated a little at 200W if the author meant it to be a working power, not a peak power. The combined 24V power supply is conservatively 192W. Buck converter efficiency in the Ruideng isn't specified but is not likely to be much better than 90% so the output power is going to be around 173W. The input voltage to the Ruideng must be 10% higher than the maximum output voltage. So the maximum output voltage will be pretty close to that specified by the author (42V). A conservative maximum output current is approximately 4A at 42V. Pretty good actually and sure to be more than most circuits will need.Inexpensive DC-DC converters typically have between 50mV and 100mV of ripple between 50KHz and 100Khz so be aware of that if you plan to use this power supply on sensitive radio or Op-Amp circuits. From experience the power supply design presented here works extremely well for most analog and digital projects. But it can cause some very weird problems with high impedance or noise sensitive circuits.This is a good Instructable for a nice power supply that looks really cool. It can be used globally with only a power cord change. Some might find the digital voltage and current increments a bit limiting but you really don't need exact voltages when good design practices are used. Close enough should be good enough for most projects.NetZener

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  • netzener commented on natantus's instructable NeoClock8 months ago
    NeoClock

    A labor of love. That's what makes a difference between a project that's fun to look at and read about, and one that is not. Thanks for putting in the many unpaid hours it took to make it happen.NetZener

    View Instructable »
  • netzener commented on roaldh's instructable Kids Kitchen That Says BEEP8 months ago
    Kids Kitchen That Says BEEP

    This is an amazing project and I loved the story on how it came about. I'm totally with you in that it was much easier to adapt a Ikea product instead of building from scratch. That decision makes it very easy for others to build one. Well done!

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  • netzener commented on Nikus's instructable Doter - Huge Arduino Based Dot Matrix Printer8 months ago
    Doter - Huge Arduino Based Dot Matrix Printer

    If you have plans to study engineering at uniwersytet you should definitely go. You would be very good at engineering design.

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  • netzener commented on natantus's instructable NeoClock8 months ago
    NeoClock

    Awesome project and excellent Instructable. You've included everything that a reader would need to build the clock and listed the references for all the parts/software used which is great. I wish everybody did that. I love perfboard construction which means anybody can do it without having to wait for a PCB to come back. I know from experience that to document everything as well as you have takes a LOT of time and effort.This is just a really good job on a very useful project.NetZener

    View Instructable »
  • Piezoelectric Nanofiber Electricity Producing Shoes

    Ha. Yes that would be hard to explain. Especially after the shoe bomber incident and the young lady from MIT that almost go shot wearing a harmless LED blinker on her blouse. But you are wise to ask. No, it doesn't work. The author is having us on a bit, I think :)

    I think the author is putting us on.Nano-fine Barium Titanate has to be sintered into a crystal at 1200 Deg C in order for piezoelectric properties to exist. You can't sprinkle it between two pieces of PCB and expect to produce a voltage under pressure. You need a crystal lattice for that and fine particles smoothed out with Methanol do not magically blend into a crystal.The scope trace shown is just displaying 462uV of noise. There's no specification for the average voltage per cell with respect to applied force. None of the photographs or descriptions show the device installed in a shoe or connected to a charging circuit. You can't connect a piezo device to a battery and expect it to charge the battery. It's a lot more complicated than that, even if it didn't require a 10,000 mi...

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    I think the author is putting us on.Nano-fine Barium Titanate has to be sintered into a crystal at 1200 Deg C in order for piezoelectric properties to exist. You can't sprinkle it between two pieces of PCB and expect to produce a voltage under pressure. You need a crystal lattice for that and fine particles smoothed out with Methanol do not magically blend into a crystal.The scope trace shown is just displaying 462uV of noise. There's no specification for the average voltage per cell with respect to applied force. None of the photographs or descriptions show the device installed in a shoe or connected to a charging circuit. You can't connect a piezo device to a battery and expect it to charge the battery. It's a lot more complicated than that, even if it didn't require a 10,000 mile walk to charge one 3V Lipo battery. There not that much energy in the walking around people typically do.I can't make any scientific sense out of Step 6. Based on the size of the PCB shown there is no way I could get 8 of them in a shoe my size, and I wear a big shoe.So, I think this article is a bit of science humor.NetZener

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  • netzener commented on DChaurangi's instructable LED VU-Meter With Arduino UNO8 months ago
    LED VU-Meter With Arduino UNO

    Is that a home-built Arduino Uno in the video?

    I liked this article. I like the perfboard construction. Be sure to watch the video because the LEDs look cool. BUT the most interesting part is it looks DChaurangi is using a home made Arduino Uno. Most people just buys those things factory made and have no idea how they work. It looks like DChaurangi made his own. And hey, DChaurangi if you made that Arduino I think you should feature it in the article because that's cool and unusual.NetZener

    Why does the mic schematic show two 10K resistors in parallel. Could someone use a single 4.7K resistor instead?

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  • netzener commented on Nikus's instructable Doter - Huge Arduino Based Dot Matrix Printer8 months ago
    Doter - Huge Arduino Based Dot Matrix Printer

    When I watched the video of the Doter in operation I couldn't help but smile. Seriously, if you read this article DO NOT skip the video. It's the most fun I've had on Instructables in a long time. You have to see it in operation to fully appreciate it.This is an excellent article and it contains all of the information you need to build one yourself. I really like that Nikus told the story on how the project came to be. That is more interesting to me than the instructions because I learn more hearing what happened on the journey. I love analog electronics and really liked that this project was designed as a complete system, not thrown together from a bunch of ICs and software downloaded from the Internet. So Thank You, Nikus.I also like that the PCB portion of the article wasn't a...

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    When I watched the video of the Doter in operation I couldn't help but smile. Seriously, if you read this article DO NOT skip the video. It's the most fun I've had on Instructables in a long time. You have to see it in operation to fully appreciate it.This is an excellent article and it contains all of the information you need to build one yourself. I really like that Nikus told the story on how the project came to be. That is more interesting to me than the instructions because I learn more hearing what happened on the journey. I love analog electronics and really liked that this project was designed as a complete system, not thrown together from a bunch of ICs and software downloaded from the Internet. So Thank You, Nikus.I also like that the PCB portion of the article wasn't a commercial, just a vendor that was part of the project and Nikus even gives the proper mention that PCBway helped a little bit with the cost. That is the right thing to do.Every single piece of information you need to build a Doter is included in the article. I enjoyed reading about it and seeing it in action.NetZener

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  • Add an Arduino-based Optical Tachometer to a CNC Router

    This is excellent work. Your article is very complete, solves a real problem, and gives credit where it's due. Brings tears to my eyes. I'm so glad you took the time to write the article. Doing those step-by-step photos isn't easy because sometimes you just get going and before you know it you're saying, "Aggggh! I should have taken photos of that" but its too late. The LED mount fabrication was most fun to observe. I'm not a fan of 3D printing but for your project it seems to have worked well.This was a great article and is right on with the spirit of the Instructables site.NetZener

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  • Twitter Sentiment Analysis With Raspberry Pi

    This is a nice article on a subject not too many folks know about outside of marketing and public relations. Most of the folks experimenting with opinion mining just use a computer to display the results but running the libraries and Twitter API and adding the LED's was a fun idea.Using a breakout cable and providing a schematic or connection drawing would make it easier for others to see how to attach the LEDs if they are new to Pi hardware interfacing. A bit more detail on how to install and run the application would have been nice too.Really short but interesting.NetZener

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  • How to Make Low Pass Filter for Subwoofer With NE5532 IC | DIY ( ELECTROINDIA )

    Based solely on the information presented here, how is someone supposed to build this circuit? There is no schematic, PCB layout, theory of operation, or specifications. There's no information presented here that is useful.At the moment all I see is an assembly guide for a circuit no one else can make and an advertisement for a PCB manufacturer.NetZener

    Well explained? I disagree. There's virtually no explanation in this article at all.But yes, the photos are nice.

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  • netzener followed Computers channel 8 months ago
  • netzener made the instructable DIY Relay Board8 months ago
    DIY Relay Board

    Completed construction and testing of an Opto-Isolated Relay module similar to the one covered here. I made a few changes to suit my design style and parts inventory. Instead of a 4N35 Opto-isolator, I elected to use a 4N32 to take advantage of the much higher CTR provided by an internal Darlington pair. I'm using this module with an Arduino Nano and designed an input current of 2mA at 5V and 1mA at 3.3V (for use with Raspberry Pi I/O if desired) via R1. I used a 2N2222 transistor to drive the relay in honor of my favorite transistor of all time, plus I have a bunch of them in inventory. The relay circuit is designed to provide 1mA drive current (R2) and includes a pull-down (R3) to improve turn-off speed and keep noise from propagating onto the relay in noisy environments when the opto...

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    Completed construction and testing of an Opto-Isolated Relay module similar to the one covered here. I made a few changes to suit my design style and parts inventory. Instead of a 4N35 Opto-isolator, I elected to use a 4N32 to take advantage of the much higher CTR provided by an internal Darlington pair. I'm using this module with an Arduino Nano and designed an input current of 2mA at 5V and 1mA at 3.3V (for use with Raspberry Pi I/O if desired) via R1. I used a 2N2222 transistor to drive the relay in honor of my favorite transistor of all time, plus I have a bunch of them in inventory. The relay circuit is designed to provide 1mA drive current (R2) and includes a pull-down (R3) to improve turn-off speed and keep noise from propagating onto the relay in noisy environments when the opto-isolator output is off. I like to see when the relay is commanded on so I included an LED that lights when Q1 is on. I prefer 12V relay power so I used a 12V relay instead of a 5V relay so that the 5V regulator could be omitted. The relay I had in stock provides separate NC/NO contacts which I find useful in a lot of machine control situations where the NC and NO circuit aren't electrically common. I used a 1N4001 diode for relay flyback suppression because I had a lot of them in inventory. The diode PIV is 50V which is more than sufficient when the relay is energized with 12V and the diode is fast enough to suppress the flyback voltage to a peak below 1V.Specifications:Digital Input Voltage: 3.3V @ 1mA or 5V @ 2mAPower Supply Voltage: 12V @ 36mARelay Output Load: 30VDC @ 5A or 250V @ 5A resistive loads 30VDC @ 2A or 250V @ 2A inductive loadsSet/Release Time: 10msIsolation Voltage: 2000V between relay contacts and relay driver 5000V between relay driver and digital inputPhotos attached below.

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  • netzener made the instructable DIY Relay Board8 months ago
    DIY Relay Board

    Completed construction and testing of an Opto-Isolated Relay module similar to the one covered here. I made a few changes to suit my design style and parts inventory. Instead of a 4N35 Opto-isolator, I elected to use a 4N32 to take advantage of the much higher CTR provided by an internal Darlington pair. I'm using this module with an Arduino Nano and designed an input current of 2mA at 5V and 1mA at 3.3V (for use with Raspberry Pi I/O if desired). I used a 2N2222 transistor to drive the relay in honor of my favorite transistor of all time, plus I have a bunch of them in inventory. The relay circuit is designed to provide 1mA drive current (R1) and includes a pull-down (R2) to improve turn-off speed and keep noise from propagating onto the relay in noisy environments when the opto-isolat...

    see more »

    Completed construction and testing of an Opto-Isolated Relay module similar to the one covered here. I made a few changes to suit my design style and parts inventory. Instead of a 4N35 Opto-isolator, I elected to use a 4N32 to take advantage of the much higher CTR provided by an internal Darlington pair. I'm using this module with an Arduino Nano and designed an input current of 2mA at 5V and 1mA at 3.3V (for use with Raspberry Pi I/O if desired). I used a 2N2222 transistor to drive the relay in honor of my favorite transistor of all time, plus I have a bunch of them in inventory. The relay circuit is designed to provide 1mA drive current (R1) and includes a pull-down (R2) to improve turn-off speed and keep noise from propagating onto the relay in noisy environments when the opto-isolator output is off. I like to see when the relay is commanded on so I included an LED that lights when Q1 is on. I prefer 12V relay power so I used a 12V relay instead of a 5V relay so that the 5V regulator could be omitted. The relay I had in stock provides separate NC/NO contacts which I find useful in a lot of machine control situations where the NC and NO circuit aren't electrically common. I used a 1N4001 diode for relay flyback suppression because I had a lot of them in inventory. The diode PIV is 50V which is more than sufficient when the relay is energized with 12V and the diode is fast enough to suppress the flyback voltage to a peak below 1V.Specifications:Digital Input Voltage: 3.3V @ 1mA or 5V @ 2mAPower Supply Voltage: 12V @ 36mARelay Output Load: 30VDC @ 5A or 250V @ 5A resistive loads30VDC @ 2A or 250V @ 2A inductive loadsSet/Release Time: 10msIsolation Voltage: 2000V between relay contacts and relay driver5000V between relay driver and digital inputPhotos attached below.

    View Instructable »
  • netzener made the instructable DIY Relay Board8 months ago
    DIY Relay Board

    Completed construction and testing of an Opto-Isolated Relay module similar to the one covered here. I made a few changes to suit my design style and parts inventory. Instead of a 4N35 Opto-isolator, I elected to use a 4N32 to take advantage of the much higher CTR provided by an internal Darlington pair. I'm using this module with an Arduino Nano and designed an input current of 2mA at 5V and 1mA at 3.3V (for use with Raspberry Pi I/O if desired). I used a 2N2222 transistor to drive the relay in honor of my favorite transistor of all time, plus I have a bunch of them in inventory. The relay circuit is designed to provide 1mA drive current (R1) and includes a pull-down (R2) to improve turn-off speed and keep noise from propagating onto the relay in noisy environments when the opto-i...

    see more »

    Completed construction and testing of an Opto-Isolated Relay module similar to the one covered here. I made a few changes to suit my design style and parts inventory. Instead of a 4N35 Opto-isolator, I elected to use a 4N32 to take advantage of the much higher CTR provided by an internal Darlington pair. I'm using this module with an Arduino Nano and designed an input current of 2mA at 5V and 1mA at 3.3V (for use with Raspberry Pi I/O if desired). I used a 2N2222 transistor to drive the relay in honor of my favorite transistor of all time, plus I have a bunch of them in inventory. The relay circuit is designed to provide 1mA drive current (R1) and includes a pull-down (R2) to improve turn-off speed and keep noise from propagating onto the relay in noisy environments when the opto-isolator output is off. I like to see when the relay is commanded on so I included an LED that lights when Q1 is on. I prefer 12V relay power so I used a 12V relay instead of a 5V relay so that the 5V regulator could be omitted. The relay I had in stock provides separate NC/NO contacts which I find useful in a lot of machine control situations where the NC and NO circuit aren't electrically common. I used a 1N4001 diode for relay flyback suppression because I had a lot of them in inventory. The diode PIV is 50V which is more than sufficient when the relay is energized with 12V and the diode is fast enough to suppress the flyback voltage to a peak below 1V. Specifications:Digital Input Voltage: 3.3V @ 1mA or 5V @ 2mAPower Supply Voltage: 12V @ 36mARelay Output Load: 30VDC @ 5A or 250V @ 5A resistive loads 30VDC @ 2A or 250V @ 2A inductive loadsSet/Release Time: 10msIsolation Voltage: 2000V between relay contacts and relay driver 5000V between relay driver and digital inputPhotos attached below.

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  • netzener's instructable 8 Transistor Stereo Amplifier's weekly stats: 8 months ago
    • 8 Transistor Stereo Amplifier
      712 views
      29 favorites
      2 comments
  • netzener commented on yahyatawil's instructable How to Make a Circuit Board With EasyEDA8 months ago
    How to Make a Circuit Board With EasyEDA

    This is a PCB vendor promotion, not an Instructables project.

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  • DIY Fidget Spinner Accelerator for UNDER $2!

    I think this is another promotion of a PCB vendor.

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  • netzener commented on CristhianM2's instructable Infrared Control 3 Channels CD40178 months ago
    Infrared Control 3 Channels CD4017

    This project doesn't appear to be any more than a PCB vendor promotion. The circuit described serves no clear purpose and even the author describes it as non-functional.

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  • Make Digital Voltmeter Ammeter Voltage Current Meter With JLCPCB

    This project doesn't appear to be any more than a PCB vendor promotion.

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  • How to Make a Professional Looking Proximity Sensor

    This project doesn't appear to be any more than a PCB vendor promotion.

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  • Make Your Own PCBs With JLCPCB

    This is project doesn't appear to be any more than a PCB vendor promotion.

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  • netzener commented on SayantanM4's instructable DIY Relay Board8 months ago
    DIY Relay Board

    Agreed. I show 800uA worst case base current on T1 at 70 DegC is sufficient to hold T1 in sufficient saturation for 30mA relay hold current between 0 DegC and 70 DegC. At 25 Deg C you are probably getting around 2mA on the Base of T1 which is more than enough to do the job.As you know these IRLED-Phototransistor isolators aren't digital devices. They have a transfer function from input to output called the Current Transfer Ratio (CTR). A given forward current on the LED results in a photo-transistor current in proportion to the CTR for a given temperature range. Worst-case CTR on the MCT2E is 20% across the full operating temperature range. So for a 4mA forward current on the IRLED, the current in the photo-transistor is estimated at 800uA minimum. I measured 1.2mA on my 4N35 at ...

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    Agreed. I show 800uA worst case base current on T1 at 70 DegC is sufficient to hold T1 in sufficient saturation for 30mA relay hold current between 0 DegC and 70 DegC. At 25 Deg C you are probably getting around 2mA on the Base of T1 which is more than enough to do the job.As you know these IRLED-Phototransistor isolators aren't digital devices. They have a transfer function from input to output called the Current Transfer Ratio (CTR). A given forward current on the LED results in a photo-transistor current in proportion to the CTR for a given temperature range. Worst-case CTR on the MCT2E is 20% across the full operating temperature range. So for a 4mA forward current on the IRLED, the current in the photo-transistor is estimated at 800uA minimum. I measured 1.2mA on my 4N35 at approximately 70 DegC +/- 5 Deg C which is pretty close to the datasheet.NetZener

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  • netzener commented on SayantanM4's instructable DIY Relay Board9 months ago
    DIY Relay Board

    Yes. You definitely want transistor T1 to saturate so that transistor dissipation is minimized. Most of these 12V relays have a holding current of around 30mA. Using the BC548 data sheet as a guide for saturated collector current somewhere 10mA and 100mA, the 1K resistor was a good choice.But at 1.2V LED drop with a 1K resistor the forward current is about 4mA. I was curious if the 1K resistor would allow enough light for the opto-transistor to conduct the 4mA of saturation current needed for T1. At 10mA LED current (330 to 390 Ohm resistor), the current transfer to the opto-transistor is between 6ma and 8mA depending on temperature which is perfect for T1. But at 4mA LED current (1K resistor), current transfer to the opto-transistor is only about 2mA to 3mA depending on temperatu...

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    Yes. You definitely want transistor T1 to saturate so that transistor dissipation is minimized. Most of these 12V relays have a holding current of around 30mA. Using the BC548 data sheet as a guide for saturated collector current somewhere 10mA and 100mA, the 1K resistor was a good choice.But at 1.2V LED drop with a 1K resistor the forward current is about 4mA. I was curious if the 1K resistor would allow enough light for the opto-transistor to conduct the 4mA of saturation current needed for T1. At 10mA LED current (330 to 390 Ohm resistor), the current transfer to the opto-transistor is between 6ma and 8mA depending on temperature which is perfect for T1. But at 4mA LED current (1K resistor), current transfer to the opto-transistor is only about 2mA to 3mA depending on temperature. At the high end of the temperature range, T1 may not saturate when turned on. Perhaps that's why you mentioned a Darlington transistor.I was just curious about your experience with the circuit and the reason for choosing the values you did. Thanks for the response!NetZener

    By line voltages I'm assuming that means 120/220V AC and that a relay with an 120/220V energizing coil would be used. If that is the case the design presented would not work. The opto-isolator output and switching transistor are designed for DC and would instantly self-destruct at AC line voltages. The circuit would need to be redesigned using an opto-isolator with a zero-cross triac output and most likely an external triac to drive the 120V/220V relay coil. But after the redesign, the relay board could only be used at line voltages. I think the author intended the relay board to be suitable for most any kind of switch control be it low/line voltages, AC or DC. The design presented does that pretty well.

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  • netzener commented on Adamneareva's instructable DIY Class a Amplifier9 months ago
    DIY Class a Amplifier

    In the 1960s when power transistors were new and expensive, a Class A amplifier wasn't unusual to find in hobby periodicals. They were simple and inexpensive, and very fun to operate just like the amplifier you built and love. Back then, though, the speaker was connected where you have the 33 Ohm resistor. The thinking then was that if you have to waste power when there is no signal, you may as well dissipate it in the speaker coil instead of a resistor. I built your circuit using two 270K Ohm resistors and the speaker in place of the 33 Ohm resistor. Just 5 components. With 0.35Vpp input, the output power from the speaker was almost 1W. Extremely loud.The disadvantage is that with no signal, the speaker coil heats up so a power rating of 1W or better is required.I'm assuming you...

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    In the 1960s when power transistors were new and expensive, a Class A amplifier wasn't unusual to find in hobby periodicals. They were simple and inexpensive, and very fun to operate just like the amplifier you built and love. Back then, though, the speaker was connected where you have the 33 Ohm resistor. The thinking then was that if you have to waste power when there is no signal, you may as well dissipate it in the speaker coil instead of a resistor. I built your circuit using two 270K Ohm resistors and the speaker in place of the 33 Ohm resistor. Just 5 components. With 0.35Vpp input, the output power from the speaker was almost 1W. Extremely loud.The disadvantage is that with no signal, the speaker coil heats up so a power rating of 1W or better is required.I'm assuming you used a 0.1uF input coupling capacitor so that your music source wouldn't overload the amplifier. Some of the signal is dropped by the capacitor so that a volume control or resistor divider isn't needed.If it's of interest to you, try the changes I described above and see if your "not very powerful" amplifier doesn't blow the doors off. Your amplifier is better than you think :)NetZener

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  • netzener commented on SayantanM4's instructable DIY Relay Board9 months ago
    DIY Relay Board

    I love breadboard projects and this is a good one for those interested in home automation or machine control. The use of an opto-isolator is right on as your controller (and by extention the user) must be protected from potential exposure to hazardous voltages or currents. The isolator and separate 12V relay supply prevents getting relay transients in the control supply resulting in system errors that are hard to troubleshoot. Good design and looks cool!What made you choose 1K resistor values for R1 and R2?NetZener

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  • netzener commented on thelonelyprogrammer's instructable Arduino Tutorial : Mini Piano9 months ago
    Arduino Tutorial : Mini Piano

    I think this is a great project on Instructables. Its simple, doesn't require special tools or parts, it looks cool, and its musical. This is definitely a great project for someone new to Arduino, or someone looking for a project that's fun to do with kids. I'm glad you included a video to go with the project as that highlights what to expect when the project is powered up and loaded up.NetZener

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  • PIR Light Switch(or Any AC Device) Without Microcontroller

    You had the right idea for C1 and C2. 7805 manufacturers recommend a small MLCC cap (usually 0.33uF) as close as possible to the input pin when the regulator is remote from the power supply filter capacitor. In your design that recommendation certainly applies. A small MLCC cap (usually 0.1uF) as close as possible to the output pin is recommended in all cases to prevent ringing and oscillation on the regulator output. I would definitely use both of those capacitors in your layout when a 7805 is installed. You were wise to include them.

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  • netzener commented on Be_Learner's instructable DIY Bike Light's9 months ago
    DIY Bike Light's

    Your project is right on with the spirit of Instructables. This is a good example of a quick and simple DIY for the fun of it project. Nothing fancy, common materials, something anybody can try. I like it. Awesome!

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  • netzener's instructable One Tube AM Radio's weekly stats: 1 year ago
    • One Tube AM Radio
      7,583 views
      97 favorites
      17 comments
  • netzener commented on netzener's instructable Neon Goofy Lite2 years ago
    Neon Goofy Lite

    The original transformer was a center taped 1K ohm primary and a 100K ohm secondary. E-core laminated iron.NetZener

    Those were so cool. These days I use spray paint and sometimes a flat clear coat. Looks great but it's an extra step.NetZener

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