Doing Electronic Projects Dangerously or Die Trying - Page 1
Forum section: electronics / general

author: jonovid
author_rank: Super Contributor
timestamp: June 02, 2019, 10:24:58 am
content: here is a DIY electronics video that gets progressively more dangerous as it plays.what Do you think? is this the way to make a video that has mains electricity in its demonstrations.Top 10 ELECTRONICS PROJECTS USING TRANSISTOR AND MOSFETI just had to post this! its as if all the electronic circuits are only 12 or 9 volts!then he hooks up the AC,like its nothing to be concerned about!see the video at 8:48 and 14:22 .hay kids avoid this one!

author: apis
author_rank: Super Contributor
timestamp: June 03, 2019, 12:18:59 am
content: What bothers me is when they play around with microwave oven transformers and high voltage in a causal way without explaining the dangers of HV. There was a guy with a channel called the king of crap or something like that who would make slime in one episode and play with MOTs in the next. I think there was a kid who died after being inspired, can't find the news article now.

author: bloguetronica
author_rank: Frequent Contributor
timestamp: June 03, 2019, 02:52:44 am
content: Quote from: apis on June 03, 2019, 12:18:59 amThat is why I never dared to work with MOTs. Very high-voltage and high-current stuff. They can be more dangerous than the transformers you find on TV sets, due to the high-current factor. The available current is more than enough to kill, even though the voltage is lower.kind regards, Samuel Lourenço

author: tkamiya
author_rank: Super Contributor
timestamp: June 03, 2019, 02:55:14 am
content: I am often surprised people don't die from these silly experiments.Once I've seen a video where someone connects 9V batteries, over 200 of them in series and draws an arc. He laughed when his multi-meter couldn't measure the total voltage. For brief moment, long enough to kill, a power source like that can dispense 2KW or more.Those alligator clips aren't rated for 2KV use either. One side may be at zero potential but say connection comes lose, and you are holding 2KV dangling from your hand. Say one of the batteries fail open, same thing. Now you have two ports of varying voltage.I also saw a video of someone using pole-pig (transformer for power distribution) and drawing huge arc inside a room.This "look at ME!" attitude and You tube culture seem bottom-less when it comes to bone headed experiments.

author: dmills
author_rank: Super Contributor
timestamp: June 03, 2019, 11:24:49 am
content: I did the 9V battery thing, at school no less....They said our project had to be battery powered, so I did a tube guitar amp with 60 9V batteries in series for the plate supply, and 3 2V rechargeable cells for the filaments.The bias battery was by contrast tame, just two 9V batteries.Top tip: Insulate the batteries in blocks of 5 or 10, the case to internal doings insulation layer in the battery does not like 540V!Second top tip: If using nicads, make sure the fuse is good for breaking DC at that voltage, turns out the glass ones get 'splodey.I was however generally known to be a much better electrosmith then the teacher was, and my stuff generally kept the high tension behind plastic so was at least somewhat safe to use.Teacher was cool with it, just so long as I didn't bring the battery charger anywhere near the school (Voltage doubler off the mains, with caps chosen to provide the current limiting impedance, but at least it was touchproof with proper connectors).Regards, Dan.

author: ptricks
author_rank: Frequent Contributor
timestamp: June 03, 2019, 12:41:57 pm
content: MOT are something I don't play around with and I have worked on CRT and the flyback power supplies they use. MOT are a whole another level in that they are not only high voltage but high current.Unfortunately the, "I saw a guy on youtube do it" mentality is all too prevalent.

author: vk6zgo
author_rank: Super Contributor
timestamp: June 03, 2019, 03:33:17 pm
content: Quote from: ptricks on June 03, 2019, 12:41:57 pmMOT are just plain old transformers with a high voltage secondary.They are quite tame compared to tube transmitter HT transformers---& I'm talkingrealtransmitters here, with 3 phase HT transformers the size of a fridge, not Ham stuff!You are right, though, big Mains operated transformer type linear HT supplies are the real deal, designed to supply several (or more) amps at several kV,(or more in the case of large Radio & TV Tx), with very good regulation.TV tube EHT supplies are a mere bagatelle in comparison--- their regulation is sufficiently poor to drop radically in voltage if you get across them.I know, colour TV EHTs regulation isn't as poor as the old BW ones were, but you still have a pretty good chance of just getting away with a "scare".Get across a MOT secondary, & all your treasured test equipment will probably appear in a deceased estate sale.