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Parts Kit posted:I will shortly have (another) very old camera meter that requires 1.35Vs to operate accurately and is intended to be used with 625 size cells. Now you can get 1.35V zinc-air batteries in this size but it's a pain in the butt since it's not like local places will have it. But I have heard of people making some sort of adapter to drop the voltage of more common 1.5V button cells down to 1.35V. How the gently caress do I pull that off? I was thinking of a diode that would have a voltage drop of .15V, but gently caress if I can find one. I checked on this like 5 years ago when I got an old camera as a gift---someone sold an adapter that was a PCA with a voltage regulator (with very low quiescent current) that fit that battery footprint and accepted a smaller lithium battery. EDIT: These might be the kinds of things I was thinking of: http://www.criscam.com/mercury_battery_adapters.php http://www.amazon.com/Battery-Adapter-Camera-Exposure-Mercury/dp/B00CTNZ9H0 Also, it looks like you can also get adapter rings for zinc-air batteries to make more common batteries fit into older form factors http://www.paulbg.com/Nikon_F_meter_batteries.htm Slanderer fucked around with this message at 03:20 on Dec 31, 2015 |
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Dec 31, 2015 03:15
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Aurium posted:Yes. It is, though there are several other things that an induction coil refer to, that are completely different, like for an induction forge, induction stoves, and inductive chargers. Is that the same as this? 
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Dec 31, 2015 03:26
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DreadLlama posted:Is that the same as this? Same idea, but that schematic is missing important safety features like protection diodes.
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Dec 31, 2015 03:41
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DreadLlama posted:Is that the same as this? Absolutely. In this case, the 555 chip (and associated circuitry) is putting out a square wave. The part of the power transistor is being played by the 2n3055, which is a fine choice. There are 2 additions I'd make to the circuit.
The capacitor marked .1 is probably .1uF. A quick simulation indicates that this will result in a frequency of 3-500hz depending on how cranked your potentiometers are. Which is fine for this application.
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Dec 31, 2015 04:31
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DreadLlama posted:Is that the same as this? You're looking for a turbine ignitor. Car spark plug stuff isn't all that great, since it's working with a known gap and a reasonably small range of A:F mixtures of known dielectric, so they can constrain their energy. Gas turbines and company use WAY WAY more energy to throw longer, hotter sparks at a MUCH lower spark rate. Look at getting a replacement ignition box for a torpedo-style heater. That's about the right environment you're working in. I've worked on several turbines and other "let's put a spark into this air pipe while we blow fuel past it" projects, and the best spark sources throw a 1-2" spark at about 5-15Hz.
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Dec 31, 2015 04:49
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Slanderer posted:I checked on this like 5 years ago when I got an old camera as a gift---someone sold an adapter that was a PCA with a voltage regulator (with very low quiescent current) that fit that battery footprint and accepted a smaller lithium battery.
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Dec 31, 2015 21:35
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babyeatingpsychopath posted:You're looking for a turbine ignitor. Car spark plug stuff isn't all that great, since it's working with a known gap and a reasonably small range of A:F mixtures of known dielectric, so they can constrain their energy. Aurium posted:The capacitor marked .1 is probably .1uF. A quick simulation indicates that this will result in a frequency of 3-500hz depending on how cranked your potentiometers are. Which is fine for this application. I don't know what I'm talking about but could I decrease the frequency and increase the spark gap if I installed a different capacitor?
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Dec 31, 2015 23:57
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DreadLlama posted:I don't know what I'm talking about but could I decrease the frequency and increase the spark gap if I installed a different capacitor? Frequency on a 555 is a function of the resistors and capacitors. Increasing the length of spark produced is a function of the coil you use and its operating voltage. Longer sparks require higher voltage. Note that there's another half of the circuit not in your picture. The ignition coil outputs to a spark device, either a spark plug or an ignitor lead. The ignition coil you have dictates how powerful your spark is, along with the gap on the ignitor/spark plug. I strongly suspect that the 15Hz rate on the ignitors we were using was more because they had to charge big coils than because it was an "ideal" frequency.
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Jan 1, 2016 00:58
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Parts Kit posted:Yeah, I've seen some of those before but was mulling over making my own since they are $40. Since you need to roll your own low-quiescent current voltage regulator in a package that fits securely in the battery holder (While being shock resistant), $40 is absolutely nothing (especially considering you only need to buy it once). To make a good one of these you almost certainly need access to a machine shop, and then you'll have to integrate a PCA (since only SMT parts will be small enough).
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Jan 1, 2016 02:45
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Can I make something "good enough" with salvaged auto parts? 20' of 1/4" tube is $30 (https://www.homedepot.ca/en/home/p.1000416310.html). My college physics teacher showed me his tesla coil, it was just pretty much 11~15 turns of copper tube, a great many turns of copper wire, some capacitors and a neon sign transformer. I have copper tube laying around already for the gasifier, it's not impossible for me to copy his design. I don't remember the exact circuit configuration but between this thread and the rest of the internet I should be able to figure it out. But on the other hand replacement ignition coils for torpedo heaters are in the $80 range on E-bay. Given that my interest in electronics is only a means to an end (and I mean that as no affront to you or your hobby), what would you recommend as my best course of action? DreadLlama fucked around with this message at 04:31 on Jan 1, 2016 |
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Jan 1, 2016 03:10
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DL, you're going about this all wrong. Rig up the gassifier and just hook the gas line to a boiler. Then rig up an easy home machined steam generator and test it without even measuring RPMS or attaching it to any kind of load like this guy: https://www.youtube.com/watch?v=6RSg5yZJ5wk See, don't even need to worry about recondensing, safety, or even effectively measuring output in any way. 1kW, bam, done and done. That's enough to run a whole house forever and also heat it. Steam heat. Dunno if he ever got anywhere with this. Also I think the designs where the gassifier uses it's own output to pyrolize are pretty cool, and it's a cool idea in general. Kind of reminds me of old coal furnaces where you just load up the chute or whatever and it basically is always on, just a hell of a lot more efficient and with less soot and poo poo vomiting out everywhere. I'd actually be interested in doing something like this myself, except it's extremely illegal to DIY anything and even if I had pros do it there's a lot of regulations around here because apparently you can blow up the block doing poo poo like this.
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Jan 1, 2016 18:03
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DreadLlama posted:Can I make something "good enough" with salvaged auto parts? Was it tube or very low-gauge wire? If it was tube, was it for water-cooling purposes? (Is it a good idea to run water directly through a transformer winding?) The pronounciation of "turbine" at the start made my eye twitch a little BattleMaster fucked around with this message at 20:35 on Jan 1, 2016 |
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Jan 1, 2016 20:30
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I remember that the primary was 1/4" copper tubing. He had 16 turns in total and could change the number of turns he used by re-positioning an alligator clip. 11~13 were generally the best but for some reason the day he brought it into class, 14 turns was producing the longest sparks and he stated that this was anomalous several times. I saw the tube edge on. It was hollow and had writing stamped on the side of it. It was definitely tube. SniperWoreConverse posted:DL, you're going about this all wrong. Rig up the gassifier and just hook the gas line to a boiler. Then rig up an easy home machined steam generator and test it without even measuring RPMS or attaching it to any kind of load like this guy: I never stated that I was planning to use jet exhaust heat for pyrolysis. Good eye. Poe's law may be applicable here. I apologize if this in inaccurate, but it appears to me that you're implying that I am playing it fast and loose with regards to safety. But my assumption is based on my opinion that the guy in the youtube video you linked doesn't appear to mind having a lot of high pressure steam next to his bedroom, and that therefore he is an idiot. I have not yet thought of the correct arrangement of pulley ratios, bushings and flyball governors that will ultimately be necessary. I recognize that I will need to do so at some point, but first I need to build a wood pyrolyzer. In order to do that, I need an ignition source.
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Jan 2, 2016 02:05
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DreadLlama posted:In order to do that, I need an ignition source. I've gotten stuff like this that makes very fun sparks (found in this very thread somewhere a while ago): http://www.ebay.com/itm/NEW-DC-3V-t...EAAAOSwCQNWeU6l Although I haven't tried to set things on fire with it yet, I'm sure you can do that and anything else dangerous you could possibly want to with it. Hook it up to a suitable DC source and it makes a very fun loud spark at regular intervals. Easiest way to shock yourself since forks and outlets! After that you need only consider the necessities of not over-exploding yourself and/or dying from CO poisoning with a wood gasifier. I think FEMA at one point made a great how-to on those for use in the event of a petroleum shortage before/during/after WWIII. Should be a PDF floating around out there somewhere. High voltage, fire, explosive/poisonous gases... Fun! You should post photos to the OSHA.jpg thread as you build this, too.
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Jan 2, 2016 08:09
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Effective-Disorder posted:I've gotten stuff like this that makes very fun sparks (found in this very thread somewhere a while ago): Yeah we brought those up a page or so ago since several people in the thread got them when they came up originally and apparently most of them stopped working within a few days. I think yours and mine are the only ones still functioning  but it might not be the best for a reliable starter system.
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Jan 2, 2016 16:04
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Parallel Paraplegic posted:Yeah we brought those up a page or so ago since several people in the thread got them when they came up originally and apparently most of them stopped working within a few days. I think yours and mine are the only ones still functioning Ahh, should have known it would have come up, but didn't notice while I scanned back quickly before mentioning. I figured they weren't exactly "critical application" parts, being so cheap, so I bought two, but I didn't abuse them enough perhaps... Like I said, haven't even lit anything on fire with it yet.
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Jan 2, 2016 17:27
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I'd rather pay ~$50 once than $4 over and over again to replace something that keeps breaking.
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Jan 2, 2016 17:33
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DreadLlama posted:Can I make something "good enough" with salvaged auto parts? Yup. Just go get a salvaged ignition coil, the bigger the better. Hook it up to some flavor of 12V pulse train, making sure your pulses are as sharp as possible. Then make an ignitor with a couple of bolts in the center of your pipe. Adjust them further apart until sparks no longer happen, then spin them closer a couple of turns. It will Probably Work.
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Jan 2, 2016 17:40
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babyeatingpsychopath posted:Yup. Just go get a salvaged ignition coil, the bigger the better. Hook it up to some flavor of 12V pulse train, making sure your pulses are as sharp as possible. Then make an ignitor with a couple of bolts in the center of your pipe. Adjust them further apart until sparks no longer happen, then spin them closer a couple of turns. Not that I think it needs to be mentioned, but make sure the bolts are sufficiently insulated electrically from the pipe somehow, since it would be way easier for the spark to arc to the pipe and conduct through that to the other side. I once had a stun gun thing that would arc into your hand and out your pinky, through the plastic battery cover and directly into the battery if you held it slightly wrong. It was great because I knew how to hold it but my friends (who of course wanted to try it out because cool sparks) did not and whelp.
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Jan 2, 2016 18:46
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DreadLlama posted:I apologize if this in inaccurate, but it appears to me that you're implying that I am playing it fast and loose with regards to safety. Nah man I'm just bullshitting. I do think the way he ran that thing was probably dumb as all hell tho. Something about the idea of just venting superheated steam through a bicycle brake spinning that fast -- seems like a poor choice to me.
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Jan 3, 2016 00:42
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He is not the worst I've seen. https://www.youtube.com/watch?v=Zygs9pb_zBw Compressed hydrogen in a propane tank. edit: (from the youtube comments) quote:I'd like to add a little warning here if I could. I appreciate what you are showing but what you are actually making is a crude fuel/air bomb. Your compressor is pulling more syngas than your retort and the difference is being made up with air pulled through your system. This is evident by the fact that you can close the air feed holes on your propane setup and still burn cleanly with a blue flame (indicating very burn very close to stoichiometric). If something goes wrong somewhere (flame arrestor, backfire through the carb on an engine, etc), the flame front could reverse into your pressure container and then boom! You could test this by filling a balloon with your mixture and tossing it into a fire. If it erupts into a lazy orange fireball, you've got good safe gas with little oxygen. If it goes pop like filling a balloon with oxy/aceteline, then it's a bomb and your tank is now just like the balloon except many times more powerful. http://www.ccohs.ca/oshanswers/safety_haz/welding/storage.html posted:Never crack hydrogen cylinders since the release of compressed hydrogen may ignite by itself. DreadLlama fucked around with this message at 01:44 on Jan 3, 2016 |
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Jan 3, 2016 01:34
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DreadLlama posted:He is not the worst I've seen. wood gas isn't pure hydrogen but yeah that guy's pretty 
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Jan 3, 2016 02:07
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quote:https://youtu.be/Zygs9pb_zBw?t=546 My shopping list for the automotive scrapyard is as follows: (Biggest/cheapest/most easily accessible): ignition coil alternator turbocharger (2) exhaust tube / tailpipe Question: What do cars have instead of a 555 timer circuit? Is there something I could salvage that would negate the need for a square wave driver? Parts on E-bay are cheap, but I'm curious about why I need a driver if a car doesn't. By the way, is there a formula to determine how much insulation you'd need to not get shocked by a given voltage? Kilovolts hurt.
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Jan 3, 2016 04:05
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DreadLlama posted:Question: What do cars have instead of a 555 timer circuit? Is there something I could salvage that would negate the need for a square wave driver? Parts on E-bay are cheap, but I'm curious about why I need a driver if a car doesn't. Old cars use ignition points to generate the pulses. So basically a switch that opens and closes driven by some shaft attached to the engine. You could potentially pull this off the engine, but it'd be bulky and you'd have to spin it somehow, to no real advantage. More modern cars with electronic ignition would have this controlled by a pin of a microcontroller that is doing things like reading crankshaft position, fuel throughput, oxygen content, emissions, throttle position, etc and deciding the optimum time to fire off the pulse. Pulling this off the car and tricking it into a good state to just continually give a pulse train would be much more effort than it would be ever save you from making your own circuit. For the wiring questions. You can look up the "dielectric strength" of a material. It's usually in like V/mm or V/in. Which you may want to do for making standoffs for your electrodes for the igniter (or you could just use any number of premade igniters) but for wire, I'd just use 30kv wire. It's widely available, and cheap. On ebay, for example, it's <$10 for 10 feet. It's usually silicone coated, so if you put roughly the same amount of sealant on any bare energized areas, you'd be fine to higher voltages than you're likely to make with an ignition coil.
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Jan 3, 2016 04:53
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Followup question: Parts of this are going to explode. When that happens, I would like the rest of it to continue to behave in a predictable manner. Therefore I prefer to use flyball governors mechanically linked to throttles over sensors with software linkage to solenoid actuators, even if the latter may be cheaper. In keeping with that theme, the following is from wikipedia:  The following is an accurate rendition of my understanding of the device. I recognize that my understanding is incorrect. I therefore appreciate your correction. "It looks like he's got the primary and secondary rigged up to work as a giant solenoid and there's a bit of iron suspended such that it closes a circuit when the coil is energized, but doing so de-energizes the coil and so the iron magnet disengages and re-opens the circuit, which re-energizes the solenoid and so the iron thing is drawn to the core again..." edit: Are there any historically-derived alternatives to the 555 design which might be resilient against my accidentally detonating an EMP in my woodstove? DreadLlama fucked around with this message at 05:32 on Jan 3, 2016 |
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Jan 3, 2016 05:28
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DreadLlama posted:Followup question: Deadman switch. You hold the switch closed to energize the 555. When it explodes, you drop the switch and the spark stops. You can stand on the switch. When you fall over, the spark stops. You can attach the switch to a cord. When your remains are propelled too far from the switch, the cord is pulled and the spark stops. Mechanical governors can also fail in hilarious ways. I wouldn't trust a flyball governor I built myself over a MCU->servo feedback loop that I'd built myself. Because that second one I can test with any number of simulation methods (pulse generator, potentiometer, software), and not something actually spinning at the designed RPM. You can also have mechanical linkages with springs on your servos. If undriven, they snap closed. The servo has just enough power to overcome the spring. Your software goes AFU? You release the button and everything goes to it's default mode. Fail safe engineering is a combination of hardware and software design.
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Jan 3, 2016 06:14
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DreadLlama posted:Parts of this are going to explode. When that happens, I would like the rest of it to continue to behave in a predictable manner. Predictable? Like the rest of it exploding? DreadLlama posted:edit: Are there any historically-derived alternatives to the 555 design which might be resilient against my accidentally detonating an EMP in my woodstove? Basically the mechanical distributor someone else mentioned earlier. https://en.wikipedia.org/wiki/Ignition_system#Mechanically_timed_ignition You're edging away from electronics at this point. I think you need to characterize exactly what your system is and all the ways it can "explode" a little more carefully before you start wandering into the controls for ignition. You can probably have a simple time rigging up an open loop with a battery, a distributor, and an ignition coil. Throw in a DC motor (12V, natch) that can turn the distributor with a simple speed controller you can buy off of eBay, you've got a good start. After you've played with that for a while, then you can mess with the design to incorporate whatever controls you want. I think you'll have better luck working your way up from there than going crazy from the get go. I think the gasifier, turbines, et al. should be figured out before you worry about electronic ignition. Edit: http://aardvark.co.nz/pjet/faq.htm I looked into this kind of thing when a friend of mine offered me an old turbocharger, after I stumbled upon the NT/6 video. I gave up on it when I figured I wouldn't have time to mess with it between classes and everything. The link above seemed to be useful at the time. Just saying, I really hope you get somewhere with this. Effective-Disorder fucked around with this message at 06:38 on Jan 3, 2016 |
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Jan 3, 2016 06:16
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I apologize. Dunning–Kruger effect. I don't know enough about this topic to fully articulate my needs. I will attempt to build a 555 circuit induction coil. Also here is a video which I find mesmerizing. I believe they use photo-relay to protect some audio component from their tesla coils. I haven't the faintest clue how anything works. https://www.youtube.com/watch?v=Ee5evlN8Bbs edit: way better video: https://www.youtube.com/watch?v=pyTC0Ggufak DreadLlama fucked around with this message at 06:56 on Jan 3, 2016 |
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Jan 3, 2016 06:35
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DreadLlama posted:I apologize. Dunning–Kruger effect. I don't know enough about this topic to fully articulate my needs. I will attempt to build a 555 circuit induction coil. You can also do that with a 555, similar to what you are thinking of doing, but instead of a pulse train, it's Lucy In The Sky With Diamonds. https://www.youtube.com/watch?v=PJpn2PzhvP4
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Jan 3, 2016 06:43
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Ok holy gently caress poo poo. Tell me how to do that with anything by Brendon Small and my ignition design is officially finalized. https://www.youtube.com/watch?v=VcW2SUuAq3I I need bass.
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Jan 3, 2016 06:58
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DreadLlama posted:Ok holy gently caress poo poo. If you make a musical ignition system, you should get a medal or something. Just make believe that the arc in this video sounds like Dethklok and you've got the idea... https://www.youtube.com/watch?v=dFSnAEmLVOw Edit: I notice that the same person who posted that video has a lot more up. I think those can give you a good idea of what goes into designing a combustion chamber for a turbine. Strongly suggest you browse the hell out of those, he does some great teardowns and explanations. Effective-Disorder fucked around with this message at 07:19 on Jan 3, 2016 |
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Jan 3, 2016 07:07
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My recent research suggests that I should ask you about the gauge and number of turns on his primary coil.
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Jan 3, 2016 07:19
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Here's someone doing music with an ignition coil. https://www.youtube.com/watch?v=_gwResvzf0E DreadLlama posted:My recent research suggests that I should ask you about the gauge and number of turns on his primary coil. Why? I mean, yes they matter, but you're not going to be able to change those things on whatever coil you get. Higher gauge means that the primary will have less resistance, which means it can take more current, which means the secondary will be able to source more current, which means hotter sparks. Number of turns has a more complicated balance to find, but for the most part any commercial transformer will have that worked out for you, and all you really "need" to know is the ratio. The ratio of primary turns to secondary turns controls primary voltage to secondary voltage. For example a 1:10 transformer would do 12v to 120v. An ignition coil is often 1:100. Most of the spark speakers use CRT flyback transformers where the gauge is small, and the turns ratio is closer to 1:250. But for making sparks you don't really care about the exact ratio either, just as long as it's high. Here's a musical 555 circuit link. http://kaizerpowerelectronics.dk/high-voltage/555-audio-modulated-flyback/ He says it's for a flyback transformer, but it should work just as well for a ignition coil. I'd still add a discrete reverse protection diode across the coil though, and at audio frequencies the 1n400x is no longer fast enough. I'd use a 1n4148, which if you compare them you'll think is tiny, but is still perfectly acceptable for this use. A word on 555 durability. It's an very durable chip. With these circuits you'd have a difficult time killing it by doing anything less than actually putting the sparks you're generating directly to it. Or wiring it up bad, like swapping power and ground.
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Jan 3, 2016 07:58
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Most of the OP images are broken and some of the instructive value is lost so it's not quite as good of a primer as people had seemed to exclaim it was earlier in the thread. I messed around with a bunch of radioshack breadboxes as a kid and have done lots of random work on automotive electronics etc but couldn't read a circuit diagram without some studying. I'd like to mess around with homebuilt electronics some as a hobby just to fool around. I had an idea for two projects I'd like to get going, one simple / introductory and another that seemed more complex and be something I work towards over time. 1st I'd like to build a solar powered USB charging station, maybe slaving it to one of those USB power packs so I could charge multiple devices from it. 2nd I'd like to build a solar powered batter / inverter device that I could run most of my living room electronics off of. This would include a PS4, a 32" flat panel TV and 1-2 laptop computers. Just googling around I can find dozens of DIY USB solar charger plans but didn't really know what would be a recommended one to start with. Also beyond that what might be a good place to start reading / look into plans to build a larger AC compatible charging device for running the higher current devices I mentioned. One issue I have with the 2nd project is that I don't know how large of a scale of panels / batteries / inverter this would require and if it would be even remotely feasible. I have an Arduino nano starter kit as a gift and might like to look into using it to setup an MPPT controlled charger for the 2nd project if I ever make it that far. Any thoughts on introductory things to work towards / reading materials / must-have tools? I've got a fair amount of automotive related tools in addition to a decent Dremel kit and have good mechanical skills, just not electrical (yet).
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Jan 5, 2016 03:12
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Aurium posted:Here's someone doing music with an ignition coil. Thank you for this. I noticed the Star Wars theme failed to reach the highest notes. I know little about arcs, but what I know about guitar strings suggests that if the electrodes were closer together, the high notes would have been audible. If true, the inverse holds that a longer spark gap would be suited to producing bass. Since spark gap length appears to be function of voltage, a higher voltage circuit is necessary. I have found a circuit on the internet which I believe could produce bass.  I like it because it is simple. https://www.youtube.com/watch?v=TMySLhZQ4mo http://www.instructables.com/id/Variable-voltage-ignition-coil-power-supply/?ALLSTEPS] babyeatingpsychopath posted:I've worked on several turbines and other "let's put a spark into this air pipe while we blow fuel past it" projects, and the best spark sources throw a 1-2" spark at about 5-15Hz. I believe this design should be sufficient for ignition requirements. However, it does not sing. The following is my attempt at rectification. To begin, dimmer switches do not produce square waves. http://www.loneoceans.com/labs/ignitioncoil/ posted:The dimmer switch must go. This is my attempt at a higher voltage singing igniter.  My first thought is to rectify mains current. Some electronic components will need to have their values altered. But I do not know which. I am soliciting instruction. It bears mentioning that one of the objectives of this project is to generate revenue via youtube and adsense. While common sense dictates that I run with an established design, my understanding of internet economics suggest I need to produce something novel in order to be successful. Therefore I find the following quote relevant: https://youtu.be/1tUSiWLyN9A?t=184
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Jan 5, 2016 04:22
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Plasma speakers are a little weird because they're not imparting vibrations onto air like a speaker or guitar string would, but actually directly inducing the vibrations in the air, so the acoustics work a little weird and different, but apparently good ones can reproduce sounds more accurately than the best speakers can (while also slowly poisoning you with ozone)
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Jan 5, 2016 04:52
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DreadLlama posted:Thank you for this. This might be counter intuitive, but the size of the spark has nothing to do with the tones it produces. In thinking about why that video is missing the higher pitch notes, there's another thing. I think I'm wrong about an ignition coil working in that circuit. In the flyback circuit. in addition to the sound you hear, that spark is also producing ultrasound at ~30khz. This 30khz tone is AM modulated (just like a radio) to produce the sound you hear. You see, transformers have a maximum frequency they efficiently couple at, it's dependent on how they're built. Ferrite transformers, like Flybacks, can be driven at very high frequencies, 10s-100s of kilohertz are no problem. Iron transformer are only happy to roughly 1khz (dependent on tons of factors). This means that you can't do the modulated carrier frequency with an iron core transformer. Now I don't know for certain, but it seems that ignition coils are iron core? I can also say that it would be fine for a car. Even an 8 cylinder car at 8k rpm would only have a frequency of 1067hz. Looking at the background oscilloscope of that ignition coil video it looks like it isn't being modulated, but is instead the different notes are made by driven it with different frequency square waves. I'm guessing that the higher frequency notes are actually too high to be effectively coupled though the ignition coil. High pitched notes are already in the range of a few khz. DreadLlama posted:
As an aside, I'd be concerned about the long term reliably of this circuit. An ignition coil is designed to take ~12v, and produce ~1200. If you feed 120v in, it'll produce ~12000. While possible, I doubt that the insulation on the secondary is built to take this voltage. I suspect it will eventually eat though the enamel on the wires, whatever potting there is and eventually short out the secondary. Or it would possibly work forever if the potting does stand up well, I just don't know. DreadLlama posted:To begin, dimmer switches do not produce square waves. Just to clear things up, square waves are not a requirement, they are simply very easy to generate in any frequency you want, and can be generated in many ways. So if you wanted your spark to be the note Concert A, you'd feed it a 440hz frequency wave. It could be sine, triangle or square, they'd all sound different, but they'd all sound like A. Think violin vs flute. Of course, to get a 440 hz square wave, you only need to tweak a couple of capacitors and resistors on a 555, or change some software in a uC. To get a 440hz sine wave you need to change how fast whatever generator you're using is spinning. Not easy to do when you have it plugged in. (okay, there IS other hardware, but it's comparatively much more expensive and difficult) DreadLlama posted:The dimmer switch must go. This is my attempt at a higher voltage singing igniter. A 555 has a max voltage of ~18v. It'll die instantly. To put more voltage on the transformer primary, you'd need could have multiple power rails, a low one for the 555, and a high one for the primary and mosfet. With a flyback transformer (as in the diagram) you'll almost certainly be overcurrenting the primary. I've never seen a circuit that puts more than like 24v on one, and it's almost always 12v. Though I'll be honest and say I don't actually know the actual max voltage that you could apply to the primary. As in that other video an ignition coil may be able to withstand 120v in this application, but as I previously mentioned, I no longer think that a ignition coil will actually work with that circuit. DreadLlama posted:It bears mentioning that one of the objectives of this project is to generate revenue via youtube and adsense. While common sense dictates that I run with an established design, my understanding of internet economics suggest I need to produce something novel in order to be successful. Therefore I find the following quote relevant: Let me be perfectly honest, This is a perfectly fine goal, and I am fine continuing to give advice. In fact you saying this helps quite a lot in narrowing down what options to give you. Earlier you mentioned the Dunning–Kruger effect. I believe this is excessive, I think you were actually suffering with a case of the XY problem. Though I think it's been nicely sorted out at this point. Also, if you have mains voltage available, and just want a dead easy source of a very hot very reliable spark, for your prototypes before you get a signing one going, look for an old style neon sign transformer. All you'd have to do is plug it in, and put 2 electrodes nearish to each other. Beware, they are FAR lethal than an ignition coil. Make sure to ground any other metal works you have so you know instantly of a fault. It has to be the old transformer style, newer electronic ones won't work for this. They're too smart, so if it says something like self adjusting, it's right out. Also, I have little reason to think that one of the heftier flybacks wouldn't work to light as well as an ignition coil, so there's that too, if you want to keep working on a singing version. Aurium fucked around with this message at 06:40 on Jan 5, 2016 |
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Jan 5, 2016 06:16
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DreadLlama posted:The dimmer switch must go. This is my attempt at a higher voltage singing igniter. Your attempt explodes 10/10 times without doing anything else. Try again! DreadLlama posted:It bears mentioning that one of the objectives of this project is to generate revenue via youtube and adsense. While common sense dictates that I run with an established design, my understanding of internet economics suggest I need to produce something novel in order to be successful. Therefore I find the following quote relevant: Too much death in this. You will electrocute yourself, or burn yourself, or somehow just disappear off the face of the earth like the Philadelphia Experiment. If you are trying to plug a 555 into rectified mains, you really should slow down and think it over again before you go anywhere near an outlet. Not even talking about "established" designs, if you don't understand general principles, you should be working with batteries (think 9V, not car battery) so that you can make mistakes that don't permanently maim you or cause everything to catch fire. You're jumping the shark with a horse in front of a wagon over the precipice of disaster. Aurium has made some very good points, but I'm starting to think that playing with neon sign transformers (they can kill) is something you don't want to jump into just yet. At least try one of those crappy little potted voltage multipliers I linked to on eBay, so you can get a feel for this stuff. Buy a couple so you can break them, they're cheap enough. You can power one off of a 9V just fine. Try igniting some hydrogen/air mixtures with that and do some basic science by observation. Work your way up by understanding power transistors and figuring out how those work. Incremental design is the key to reliable success. Nobody just pulls a system out of their rear end, it's always based on previous knowledge of proven systems and components. When you really branch off and do something new, it always involves testing and progress from the baseline up so that you have some point of comparison, or at least an idea of what to expect. You don't have a baseline, you have a concept. Someone's one-off cool thing on YouTube or Instructables is not necessarily a "proven system", at least not to you until you build an example that works, and you understand how and why it works. I don't want to discourage you from your idea, but maybe go back and think about trying to build something like the original schematic: a 555 and FET hooked up to a transformer running from a limited power supply first to get yourself acquainted with what's going on. Also read the datasheet for the 555 (and any other component you use.) If you did you'd know better than to try and use 120V there. EDIT: Hey, before you "modified" this design, did you even read the page describing it and understand what was written there? You should be asking questions about that if you don't understand. http://kaizerpowerelectronics.dk/high-voltage/555-audio-modulated-flyback/ Effective-Disorder fucked around with this message at 07:26 on Jan 5, 2016 |
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Jan 5, 2016 07:15
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Parallel Paraplegic posted:(while also slowly poisoning you with ozone)
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Jan 5, 2016 07:19
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Aurium posted:To get a 440 hz square wave, you only need to tweak a couple of capacitors and resistors on a 555, or change some software in a uC. To get a 440hz sine wave you need to change how fast whatever generator you're using is spinning. Not easy to do. Square waves forever in that case. Required or not, easier and cheaper wins (https://www.youtube.com/watch?v=ddYZITaxlTQ) Aurium posted:As an aside, I'd be concerned about the long term reliably of this circuit. An ignition coil is designed to take ~12v, and produce ~1200. If you feed 120v in, it'll produce ~12000. While possible, I doubt that the insulation on the secondary is built to take this voltage. I suspect it will eventually eat though the enamel on the wires, whatever potting there is and eventually short out the secondary. Or it would possibly work forever if the potting does stand up well, I just don't know. The producer of the instructables log I referenced earlier mentioned that ignition coils were considered so cheap as to be disposable. I have not yet contacted any local scrapyards to verify. But if one lasts for 5 years and costs $20 to replace I would consider it an acceptable maintenance cost on the same order of magnitude as carbon brush replacement. Aurium posted:Earlier you mentioned the Dunning–Kruger effect. I believe this is excessive, I think you're actually suffering with a case of the XY problem This is the highest compliment I have received in my life. I will try to live up to it. I used to have a flyback spark gap generator. It was driven by a pair of transistors on a heat sink, and ran off a car battery. I have no idea how it worked as my father built it and my mother threw it out. It didn't care about insulation and would zap you right through the leads leading to the ladder. When I was around 8 or so I was so fascinated with the sensation that I wore out the insulation and it (now/more recently used to) arc rather than spark. Said sensation was unpleasant. Therefore it may be relevant to know that I am also partially motivated by a desire to replace his with a bigger/better singing one with thicker insulation. It is my understanding that I will need transformer oil and transformer oil is mineral oil and that the cheapest form of mineral oil is baby oil. I don't have a question about this. I merely would like you to note my plan to submerge the unit in dielectric oil during your ongoing assessment of whether or not I am an idiot. Aurium posted:Also, if you have mains voltage available, Technically, I do not have access to mains voltage.  I have access to a bunch of solar panels.  And also I've got some car batteries and an inverter. I honestly don't know how similar that is to actual mains voltage.
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Jan 5, 2016 07:32
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