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Rigged Death Trap posted:Hah! Incidentally, the French in that bit with the clean leather gloves translates roughly as: "That was better." "Yeah, there wasn't an explosion." "I reckon you'd have about seven seconds to remove yourself from it."
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# ? Jan 12, 2014 02:15 |
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# ? Apr 25, 2024 18:44 |
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Smiling Jack posted:I forget if it was in Things I Won't Work With or Ignition! but someone developed a compound so sensitive it exploded if you shone a bright light on it. He noted that it's great for blowing up Raman spectrometers but that's about it. Also, it blew up if you shone fairly dim (a few milliwatts) infrared laser light on it. Which is about the gentlest thing you can do to something photographically, really. http://pipeline.corante.com/archives/2013/01/09/things_i_wont_work_with_azidoazide_azides_more_or_less.php quote:The compound exploded in solution, it exploded on any attempts to touch or move the solid, and (most interestingly) it exploded when they were trying to get an infrared spectrum of it. The papers mention several detonations inside the Raman spectrometer as soon as the laser source was turned on, which must have helped the time pass more quickly. This shows a really commendable level of persistence, when you think about it - I don't know about you, but one exploding spectrometer is generally enough to make recognize a motion to adjourn for the day. But these folks are a different breed. They ended up having to use a much weaker light source, and consequently got a rather ugly Raman spectrum even after a lot of scanning, but if you think you can get better data, then step right up. e: beaten by GWBBQ, and in the wrong thread too. Shame on me! I saw something I forgot I even owned today while cleaning out my storage unit. A voltage regulator vacuum tube. A what, you say? http://www.radiomuseum.org/tubes/tube_0a3.html It's basically a tube full of gas chosen to have the right ionization voltage. For a reasonably wide range of currents, it will maintain roughly the same voltage across the two terminals. So you use this to bias another tube that actually regulates the voltage supplied to the loads in your circuit. They were obsolete decades before zener diode regulation became obsolete, which was decades ago. kastein has a new favorite as of 03:35 on Jan 12, 2014 |
# ? Jan 12, 2014 03:26 |
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Platystemon posted:Yes, there are fires that don’t involve oxygen. In chemistry terminology, oxidation isn’t something that only oxygen can do. Oxygen isn’t even the best oxidiser. Thank you very much! That's incredibly fascinating! This sort of thing is very cool to me, but I never got too far into it in school because I suck a huge butt at math. I really appreciate you explaining it in a simple way. I'm actually aware the sun is nuclear, but I thought it was burning, too...? I actually have no idea what I was thinking. I feel dumb now.
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# ? Jan 12, 2014 05:52 |
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NLJP posted:Incidentally, the French in that bit with the clean leather gloves translates roughly as: Also, I love the light jazz soundtrack. One can only hope that's the sort of thing they had in the background while they were blasting everything they could get their hands on with disturbingly reactive chemicals. And thanks for the inergen info.
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# ? Jan 12, 2014 12:20 |
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Late, but halon is still in limited use with the US Navy. They also still stock freon.
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# ? Jan 12, 2014 16:03 |
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Hogge Wild posted:drat! So you are saying that spaceships could fight each other by using muzzleloaded black powder cannons ? That rear end in a top hat Newton would make it awfully hard to keep aligned with your target.
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# ? Jan 13, 2014 18:20 |
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Hogge Wild posted:drat! So you are saying that spaceships could fight each other by using muzzleloaded black powder cannons ? The Soviets mounted a machine gun on one of their space stations. It wasn’t muzzle‐loaded, but it was almost as impractical.
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# ? Jan 13, 2014 18:25 |
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What's the maximum thrust of a 12.7mm machine gun?
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# ? Jan 13, 2014 18:59 |
Collateral Damage posted:What's the maximum thrust of a 12.7mm machine gun? http://what-if.xkcd.com/21/
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# ? Jan 13, 2014 19:13 |
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Collateral Damage posted:What's the maximum thrust of a 12.7mm machine gun? If Wikipedia’s figures for the (23 mm‐calibre) gun are correct, it had a thrust of about 5 kN. The station only carried 32 rounds, though, so at 2000 rounds/m, it would have exhausted its ammunition in under one second. Using it for reaction control would not have been practical, to say the least. Platystemon has a new favorite as of 19:27 on Jan 13, 2014 |
# ? Jan 13, 2014 19:22 |
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Smiling Jack posted:I forget if it was in Things I Won't Work With or Ignition! but someone developed a compound so sensitive it exploded if you shone a bright light on it. A simple mixture of chlorine and hydrogen will do that; it's a common experiment in chemistry classes. Unfortunately this is the only video I can find showing it: https://www.youtube.com/watch?v=IYU7nQxdRG8
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# ? Jan 13, 2014 20:23 |
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kastein posted:I saw something I forgot I even owned today while cleaning out my storage unit. A voltage regulator vacuum tube. To expand on this: Voltage regulator tubes act basically like neon indicators. In fact, I found and built one schematic for a xenon flash strobe circuit that used a cheap neon tube from radioshack for the trigger (as you are charging the high-voltage side of the circuit, the trigger activates once the voltage reaches the required DC voltage to ionize the gas and complete the circuit). The way these things work is pretty cool. The tubes are made with an inert gas mixture and two electrodes. Inside the tube, there is some fraction of the atoms that are ionized at any given time due to random processes. A voltage is placed across the electrodes, and any free electrons are steered towards the anode, and the much bigger positive ions are dragged towards the cathode. The gas in the tubes is at a very low pressure, which means that on average a particle can travel quite a long way before colliding with another (compared to in high pressure gas)--in the presence of an electric field, this means it has a longer time to accelerate. When an ion or electron collides with another atom, it has enough energy to knock off an electron, creating another ion-electron pair, which are in turn accelerated into other atoms. Eventually electrons reach the anode, and ions reach the cathode (where they get an electron back and drift back through the tube).By using this avalanche effect, you are able to multiply the number of ions in the gas (which also makes geiger tubes possible). It also helps create the regulation effect--for a given gas mixture, there is a voltage below which the ions don't have enough energy for the avalanche process to begin. However, once you start further increasing the voltage across the tube, the current through it is limited by the finite number of ions that can be generated. This means that the voltage across the tube is also limited, which lets it regulate higher voltages down to the intended voltage. One issue with the tubes, however, is that only work with a band of currents. Too little current flowing the the tube and the ionization process ceases. Too much current and the tube can internally arc, which dramatically decreases the voltage of the tube. Super unforgiving for circuit design, I'd imagine. Another cool thing is that some voltage regulator tubes were radioactive. By putting a tiny about of some radionucleide into the tube, you can increase the average number of ions present. Although radioactive decay is inherently random, it is more reliable than random ionization, and allows you to fine-tune the voltage at which a tube turns on. For instance: http://www.goldmine-elec-products.com/prodinfo.asp?number=G18735 This idea was also applied to spark plugs, but I can't imagine it being very useful. http://www.orau.org/ptp/collection/consumer%20products/sparkplugs.htm edit: wikipedia had a link on radioactive regulator tubes: http://www.orau.org/ptp/collection/consumer%20products/electrontubes.htm Slanderer has a new favorite as of 20:30 on Jan 13, 2014 |
# ? Jan 13, 2014 20:25 |
Losing track of which thread has the most plane chat, but:Party Plane Jones posted:The Kindle daily deal for today is Red Eagles: Americas Secret MiGs, about the US aggressor training program using Soviet airframe examples (which were mostly from defectors if I recall correctly.) For $2 it's a steal.
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# ? Jan 13, 2014 23:04 |
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I'm tired of chemical talk, and found this in one of my boxes of crap I'm trying to purge. Click for huge. "Books Are Weapons In The War Of Ideas" This is an "Armed Services Edition" copy of the novel "The Asiatics" which in my limited reading of it/looking up the synopsis was a fanciful tale of a traveler and his adventures in Asia, written by a man from Wisconsin who never left America. Anyway. During World War II, there were an enormous number of new members of the US military. Evidently life, when not engaged in combat, could be rather boring. A group of book publishers got together and decided to create a program where lightweight, inexpensive books could be distributed to soldiers. Over a thousand different titles were released over a variety of genres, to appeal to recruits from all walks of life. Some were adventure books like this, some were works by major novelists, there were collections of short stories and poetry, some nonfiction stuff, humorous books, plays, and even the Merriam-Webster dictionary. At least 100 million books were printed and distributed during WWII. The most valuable single book today is apparently a copy of a Superman novel which is in demand by comic book dorks. The books were printed two at once on machines for printing magazines or catalogs and then cut in half. The top half of the page was one book, the bottom another, and then the printer would split them. They cost about a nickel each to make, with the publishers foregoing their royalties and the authors receiving one cent per printed copy. Most fell apart after repeated readings, which was just as well to the publishers and ensured that the US market wasn't flooded with these cheap paperbacks following the war. A good number survived anyway and they're not worth anything but still it's a cool piece of WWII history. It's one of those time and a place things that probably won't ever be attempted again.
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# ? Jan 14, 2014 06:31 |
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two forty posted:I'm tired of chemical talk, and found this in one of my boxes of crap I'm trying to purge. I think I've seen these in WW2 movies - maybe specifically The Big Red One. What a neat bit of history. Why are they bound in landscape anyway? Surely a regular portrait style book would take up the same amount of space.
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# ? Jan 14, 2014 14:03 |
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Mr. Flunchy posted:Why are they bound in landscape anyway? Surely a regular portrait style book would take up the same amount of space.
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# ? Jan 14, 2014 16:56 |
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Everything in this 1991 Radio Shack flyer can be done with a smartphone.
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# ? Jan 17, 2014 21:45 |
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KozmoNaut posted:Everything in this 1991 Radio Shack flyer can be done with a smartphone. My smartphone can’t put out bass like a 15″ woofer. Maybe I just need to download new drivers. Platystemon has a new favorite as of 22:14 on Jan 17, 2014 |
# ? Jan 17, 2014 21:52 |
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Smartphones have an inbuilt CB radio scanner? VVV Everybody look at Mr. "Friends with Johnny Bigblogs" down there VVV Mr. Squishy has a new favorite as of 21:59 on Jan 17, 2014 |
# ? Jan 17, 2014 21:54 |
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KozmoNaut posted:
My friend posted that on his blog and then it was on tv.
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# ? Jan 17, 2014 21:56 |
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Mr. Squishy posted:Smartphones have an inbuilt CB radio scanner? Yours doesn't?
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# ? Jan 17, 2014 22:37 |
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My phone doesn't even have a floppy drive. The future is BULLSHIT.
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# ? Jan 17, 2014 23:07 |
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I wish I could play my sweet The Police audio cassettes on my smartphone.
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# ? Jan 17, 2014 23:14 |
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If my phone had a radar detector that would be super useful, I'd just get one of those dash docks. "No officer it's just my phone in the charger"
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# ? Jan 17, 2014 23:17 |
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Pham Nuwen posted:If my phone had a radar detector that would be super useful, I'd just get one of those dash docks. "No officer it's just my phone in the charger" I've had really good results with Waze letting me know of cops up ahead. Everybody post their favorite GPS units (for cars). e: We had a TomTom One. You know why this was great? The voices you could get. I paid for two: One was Gary Busey. Like, actually Gary Busey. e2: Can't get video embedding to work for some reason. Click for YouTube. Manky has a new favorite as of 00:02 on Jan 18, 2014 |
# ? Jan 17, 2014 23:53 |
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KozmoNaut posted:
Hell without schematics I can't even be sure my iPhone has a heterodyned receiver, let alone a super heterodyne!
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# ? Jan 18, 2014 00:04 |
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It can't play my lame-o 90s CDs! gently caress smartphones! Half seriously, though, kind of gently caress smartphones. They suck as phones, but they play cute games and work as an mp3 player, so eh. I kind of don't like the touchscreens,though. I can call on a regular phone without looking, while I misdial half the time on a smartphone while trying very carefully to call someone. I even have tiny little fingers, so what the hell.
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# ? Jan 18, 2014 00:04 |
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Ensign Expendable posted:I wish I could play my sweet The Police audio cassettes on my smartphone. If I ever have children they can forget all this "modern music" poo poo, they're going to have to get by with finding SD cards with nothing but random bullshit "mixtapes" of dad music just like I did with my walkman and form their musical tastes from that.
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# ? Jan 18, 2014 00:10 |
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DicktheCat posted:Half seriously, though, kind of gently caress smartphones. They suck as phones, but they play cute games and work as an mp3 player, so eh. I kind of don't like the touchscreens,though. I can call on a regular phone without looking, while I misdial half the time on a smartphone while trying very carefully to call someone. I even have tiny little fingers, so what the hell. You sound exactly like my grandpa.
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# ? Jan 18, 2014 00:14 |
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Mr. Squishy posted:Smartphones have an inbuilt CB radio scanner? there are online scanner streaming audio sites now. Use one in your phone's browser (and hope it has someone actually streaming the channel you want in your area)
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# ? Jan 18, 2014 00:18 |
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My phone even has an IR transmitter so I can be an utter cock and sneakily switch off mates TVs during the middle of the cricket. And come to think of it, I can even plug in a mouse.
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# ? Jan 18, 2014 00:29 |
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There are different ways to access canned audio and local radio feeds on smartphones, yes, but those “RADAR detector” apps can only warn you of recurring speed traps. If the police keep moving or set up a new one you’re out of luck. Of course, real RADAR detectors become increasingly useless as police switch to LiDAR, so it’s kind of a wash.
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# ? Jan 18, 2014 00:33 |
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DicktheCat posted:
What's it like living in the twilight zone?
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# ? Jan 18, 2014 02:56 |
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kastein posted:there are online scanner streaming audio sites now. Use one in your phone's browser
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# ? Jan 18, 2014 03:19 |
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Manky posted:e: We had a TomTom One. You know why this was great? The voices you could get. I paid for two: One was Gary Busey. Like, actually Gary Busey. I had Mr T, he pitied the fool that didn't turn left in one mile.
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# ? Jan 18, 2014 03:41 |
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Mr. Flunchy posted:You sound exactly like my grandpa. Sonny, back in my day, a cell phone looked like this: Oh, I'm actually not that old, then. Oops, I guess I'm just crotchety. Seriously, though, when I was like, 9, these things were out, and you just could not destroy them. My mom dropped hers in the toilet twice. The first time, we took it apart and dried it, and it was alright, but the second time, no go. The battery was all sorts of hosed. I seem to remember they didn't get great service, though. Nothing is new. E: nothing much.
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# ? Jan 18, 2014 03:42 |
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Mr. Squishy posted:Smartphones have an inbuilt CB radio scanner? No, but you could use the Scanner Buddy app (for Android) and listen to police activity all over the globe. It's pretty sweet.
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# ? Jan 18, 2014 05:44 |
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DicktheCat posted:Sonny, back in my day, a cell phone looked like this: Have to hold it on the side to talk. You had to remove the battery to change the game in it. There was an exclusive Elder Scrolls game on it though. This was before Elder Scrolls came out with Oblivion and became a massive thing. Edit: Oh wait, that's the BEFORE N-Gage thing! Hell! Even older!
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# ? Jan 18, 2014 09:40 |
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Croccers posted:There's an N-Gage in that picture. I think that's a good failed technology thing.
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# ? Jan 18, 2014 13:54 |
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# ? Apr 25, 2024 18:44 |
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Croccers posted:Edit: Oh wait, that's the BEFORE N-Gage thing! Hell! Even older! I still have mine, I loved that phone! MP3 player that crashed my computer every drat time! :3
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# ? Jan 18, 2014 14:01 |