What started as a 4700 uF capacitor and 9 volt battery eventually became 180,000 uF of 75-volt computer grade caps mounted to aluminum buss bars hooked up to a 50 volt transformer, rectifier, and 10-bulb dim bulb limiter. Turns screwdrivers, bolts, coins, and beer cans into explosions. Two welding rods and cables makes an “electric fencing” machine. (At the time we were watching the Highlander TV series religiously.)
I’ve always wanted to connect one end of a cheap extension cord to a ground rod, and throw the other end over a 69kV primary distribution line, but never went thru with it because I didn’t think I could get far enough away quickly enough. I bet it would be one hell of a flash.
Copper clad steel wire was used as radials for vertical antennas, I believe it was also used for field telephones by the US military in WW-II
Mbe 30 years ago I saw a movie on "kite fighting" in India. I believe the combatants were working from the top of their apartment buildings.
My worst shock -- I used to scrounge old TV sets for ham radio components. Got a jolt from something which wasn't discharged, so powerful it knocked me across the room.
Many people here know that my tube amp career started at a young age, and my "parts depot" was a nearby trash dump. There were hundreds of discarded TV's, radios, and HiFi sets. I got a nearly unlimited supply of tubes, transformers and other parts including electrolytic caps from discarded electronics.
Nearly every dead console TV had a power transformer. Occasionally I found the rare transformer that had a 5U4 socket mounted on one of the end bells. I liked those "DC transformers" and grabbed every one I saw, since that's one hole I didn't have to make, and one socket I didn't have to wire. One day I found a big transformer with TWO 5U4 sockets on it. It was the only one I have ever seen. I mounted it on a crude wood box with a few caps inside and it became my bench power supply. I think it made about 350 volts.
I collected lots of electrolytics, mostly twist-loks since they were the most common in radios and TV's. Every cap I found was "tested" the only way a kid knows, charge it up on the power supply and see how big a spark it made.
Once the collection of caps grew to "way more than I could possibly use" I took all of the ugliest caps put them in an old wooden cigar box, wired their HV sections all in parallel with #14 house wire and left two "probes" of #10 wire protruding from holes in the side of the box. This was my "reusable firecracker" since it's "report" was as loud or sometimes louder than a Black Cat firecracker. It was also a means of making small electronics parts explode.
I had this device for nearly a year when "it" happened. I guess that one of the caps had enough of my crap and it shorted during a recharge. All of the other fully charged caps dumped their energy into the dead cap turning it into a volcano. This was during a period of time during my pre-teen years when my "electronics experiments" were confined to an outdoor storage shed, so I grabbed the volcano, ran to the nearby lake, and threw it in, where it probably still remains along with some other "failed experiments."
Sometime around age 25 I was shopping at Skycraft in Orlando (long ago when it was quite disorganized) when I found a big bunch of large "computer grade" caps. I asked how much and was told $1 each, or $20 for all. I resisted and only bought two, one I had a use for, and one for fun. The fun cap was 33,000 uF at 160 volts. It was about a foot tall and maybe 4 inches in diameter. I fashioned two probes out of BCH (bent coat hanger, or redneck muffler hanger) and charged it with a diode, a light bulb, and a wall cord in series. I had that "farad bomb" for several years until I stripped out one of the screw holes replacing the BCH which didn't last long.
Speaking of "What a shocker" imagine a 10 to 12 year old barefoot kid playing with hot chassis electronics in a steel storage shed with an extension cord, a bare dirt, or mud on a rainy day, floor in the south Florida rain and humidity. Shocking events were pretty common until I learned that a pair of flip flops on my feet prevented most of them.
The only bad shock came earlier in life. It was my first experience with a hot chassis radio. I had found a dead table radio in someone's trash and dragged it home. Working on the terrazzo floor (pretty cement) I took the chassis out of it's case, plugged it in to see no tubes glowing. I sat on the floor with the radio and a box full of tubes, plugged the radio in, and grabbed the chassis. I was getting a serious shock and could not let go. Fortunately my mother was nearby, and smart enough to grab the cord and rip it from the wall outlet.
That event, and another involving a shorted rectifier tube and one of those paper cased electrolytics with wires coming out of the end which stunk up the whole house got my antics banned from the house by my father and into the shed. Any electronics brought into the house had to be "working" and approved by both parents until sometime in my early teens.
The only "temporary loss of consciousness" shock came at about age 30 and involved the beach, a sailboat, and a lightning bolt. It was not a preventable event though, and would not have happened if I had NOT been so safety minded.
Copper clad is often used in ham radio and other long wire antennas. Some of the old wire used for 7200 volts here on the power poles is obviously copper clad since it is now green. All the new wire is aluminum.
Both applications need the strength of steel for the long runs, as copper will stretch over time. In the radio antenna, most of the conductivity is on the surface due to the skin effect, so the resistivity of steel is not a big issue.
When I was a kid I had a 180,000 uF 16 volt capacitor that I loved to charge and scare people with the discharge with a screwdriver or piece of metal.
Unfortunately it is really true that you can kill a capacitor with a hard discharge. My toy eventually lost its strength and was useless for that purpose of scaring people.
Unfortunately it is really true that you can kill a capacitor with a hard discharge. My toy eventually lost its strength and was useless for that purpose of scaring people.
The caps ALL came from Skycraft. And did you know the “light bulb limiter” was first invented to prevent capacitors (and rectifiers) from self-destructing in the Spark-O-Matic, before it was ever used to test amplifiers? I used mine for over 10 years, in places where 4th of July fireworks were illegal and rigorously enforced, often in plain view of the cops. Neener, neener. I did mange to grab both “swords” during an electric fencing match once - 75VDC wasn’t *that* bad but it was a surprise.
Far worse than any other shock was finding 277 volts with a *wet mop* in a commercial kitchen. 480 volt 3 phase appliance, plugged into the *floor*, under one of the steel counters, and I got the mop tangled on it. Trying to free it without seeing what happened first. Holy **** that hurt. Whole right side of my body acted funny for days. 120 has got nothing on this. After that I was never even skiddish about replacing outlets and switches “hot”. So much so that once I was installing a junction box (to add a light) on an existing conduit. Without realizing that the one emergency lighting circuit on that floor would still be active after turning off ALL the breakers in the panel at the end of the hall (this was Beta Hall at USF, BTW - probably now torn down). Didn’t get a shock, but did fall off the ladder and ruin a good pair of Klein diagonal cutters.
Far worse than any other shock was finding 277 volts with a *wet mop* in a commercial kitchen. 480 volt 3 phase appliance, plugged into the *floor*, under one of the steel counters, and I got the mop tangled on it. Trying to free it without seeing what happened first. Holy **** that hurt. Whole right side of my body acted funny for days. 120 has got nothing on this. After that I was never even skiddish about replacing outlets and switches “hot”. So much so that once I was installing a junction box (to add a light) on an existing conduit. Without realizing that the one emergency lighting circuit on that floor would still be active after turning off ALL the breakers in the panel at the end of the hall (this was Beta Hall at USF, BTW - probably now torn down). Didn’t get a shock, but did fall off the ladder and ruin a good pair of Klein diagonal cutters.
For a brief period in my 30's, I worked for an electronics manufacturing company that made TV cable boxes.
My duties were varied, including alignment and testing, and on-site construction of racks for burning-in of these boxes.
The plant had 3 phase 440V systems, of which I had to tap into for 120V lines for the burn-in racks.
They told me that they couldn't kill the area where the racks were to be built - I had to work with live 440 in the metal conduits available.
Their argument was that killing the power would hold up the assemblers working, and production, since the line was connected to their area.
Well.......
Up on a ladder, 12 feet in the air, while carefully attempting to pull a taped/insulated line through the conduit, one wire hit a burr in the (grounded) conduit cut end, right at my hand.
BOOM! 😱
Thankfully I wasn't wearing a ring on my finger, it might have melted to the conduit.
A huge blast of white light and heat blew into my face too, and the factory lights all dimmed for a moment with a large HUM.
All the girls doing assembly turned and looked at me on that ladder.
Once I got down off it, my fingers stinging and blackened, they immediately took me to the doctor for treatment.
I was compansated, likely to prevent them from being sued.
They ran such a slipshod factory operation that I was glad to leave there a few months later.
My duties were varied, including alignment and testing, and on-site construction of racks for burning-in of these boxes.
The plant had 3 phase 440V systems, of which I had to tap into for 120V lines for the burn-in racks.
They told me that they couldn't kill the area where the racks were to be built - I had to work with live 440 in the metal conduits available.
Their argument was that killing the power would hold up the assemblers working, and production, since the line was connected to their area.
Well.......
Up on a ladder, 12 feet in the air, while carefully attempting to pull a taped/insulated line through the conduit, one wire hit a burr in the (grounded) conduit cut end, right at my hand.
BOOM! 😱
Thankfully I wasn't wearing a ring on my finger, it might have melted to the conduit.
A huge blast of white light and heat blew into my face too, and the factory lights all dimmed for a moment with a large HUM.
All the girls doing assembly turned and looked at me on that ladder.
Once I got down off it, my fingers stinging and blackened, they immediately took me to the doctor for treatment.
I was compansated, likely to prevent them from being sued.
They ran such a slipshod factory operation that I was glad to leave there a few months later.
Couldn't you have run the wire first and then connected it to the live system?
In Canada (at least in this area), we use 3PH 600V - that would have sucked a lot more...
In Canada (at least in this area), we use 3PH 600V - that would have sucked a lot more...
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I did pre-wire, pre-run the burn-in racks first.
Everything had to run in metal conduit.
It was the mating of the live line that was difficult, having to stuff the line down into the junction box - when it got snagged on a burr in the box entry clamp.
The main breakers if shut off, were 100A lines too, they didn't even trip.
The resulting fireworks sparks shot 40 feet over to the assembly line, some girls screamed.
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100A at 277/480 is a LOT of potential... I'm not surprised the breaker didn't trip TBH (My first experience with breakers was FPE - They are kind of crap). My other friend Matt who's an electrician up here in Canada wouldn't touch that voltage live for double his pay. His line is effectually "It doesn't matter how much they pay, if I die on the job my family gets basically nothing (compared to my actual salary, prorated over time*)" Depending on what you touch, 277/480 can give you a 1350V shock (2Vpk), right?
I am, however, surprised that you were as lucky as you were (and I'm also quite thankful).
I am, however, surprised that you were as lucky as you were (and I'm also quite thankful).
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Indeed!
Being up 12 feet on a ladder, and experiencing that kind of blast, I'm lucky that I didn't fall - the floor was concrete.
I was partially temporarily blinded though, the flash was so white hot like staring at sunlight.
It was a lousy place to work at, crappy violations, terrible management, snotty employees.
Yet the management treated me like a prince to save their hides.
But 6 months later, we all got our Christmas bonuses December 22, and additionally I got my walking papers for some nonsense BS.
Real nice Christmas present! 😱 after I already spent a good deal on presents and had rent yet to pay.
Life... sometimes sucks.
Worst hit I ever took was when I was about 17. When I saw a TV on the curb for pickup I would go with a wheelbarrow and pick it up for parts.
I had a workbench in the garage with outlets in easy reach.
I plugged in a TV I had hauled home and it didn't power up, no picture no sound. So I reached up and pulled the plug.
I went To cut a wire, and had my hand on the chassis.
Yup, I pulled the wrong plug.
I woke up about 14' (~4.3M) in back of the bench against the floor.
I had a workbench in the garage with outlets in easy reach.
I plugged in a TV I had hauled home and it didn't power up, no picture no sound. So I reached up and pulled the plug.
I went To cut a wire, and had my hand on the chassis.
Yup, I pulled the wrong plug.
I woke up about 14' (~4.3M) in back of the bench against the floor.
When I was young, my father decided to "clean" the 23 inch B/W RCA console tv in our living room.
He did pull the plug, took the back off and decided to wipe the dust off the back of the picture tube with a dampened rag.
As I sat there, nearby on the floor, playing with my toys, I saw good old dad fly across the living room into the sofa 10 feet away.
He did pull the plug, took the back off and decided to wipe the dust off the back of the picture tube with a dampened rag.
As I sat there, nearby on the floor, playing with my toys, I saw good old dad fly across the living room into the sofa 10 feet away.
Usually what seems to happen with an aluminum mast is that it blows a bunch of small holes through the hull near the mast step and chainplates.
These days carbon fiber masts are generally cheaper than aluminum, so they're getting more common. You'd think they'd be fine in a thunderstorm... but they're not. Usually what happens is that it vaporizes most of the resin in the mast, and all or part of the mast ends up looking like black hair. There are some pictures of an OK dinghy that got struck by lightning while being sailed. Quite impressive.
And since it's in line with this thread, here's a fun picture for y'all.
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I spent a lot of time in my teens on one of two 34 foot sailboats with aluminum masts. The common practice then was to hang chains from the side stays into the water thinking that it would save the hull in a strike. Well some lightning strikes are bigger than others and those over the Atlantic near Florida are usually BIG!
In this case I was about a mile offshore off Ft. Lauderdale beach on a 14 foot Hobie Cat when I saw the storm brewing over the mainland. Most of the dedicated small sailboat crazies viewed this as an opportunity for a wild ride, and skirted the edge of the storm for some fast and unpredictable winds. Sometimes I engaged in this practice as well.
I worked the 4 PM to midnight shift at Motorola and went to the beach in the morning before work nearly every weekday with decent wind. It was almost time to leave, so I headed in.
I had the boat on the trailer and I was putting the 20 foot aluminum mast in its cradle while standing barefoot on the wet sand. The next thing I know I'm lying on my back looking up at people asking if I was OK or "Is he dead?" I was about 5 feet from the boat. Lightning had struck the water tower across the street and induced enough voltage in my "antenna" to light me up.
Once I figured out what happened and recovered I hastened my exit. If I was still there when the paramedics got there I would have been late for work, or even in the hospital. I went to work as usual and the only side effects were a mild headache and a metallic taste in my mouth.
Speaking of carbon fiber and shocking situations...
An idiot in an area not far from where I used to live attempted to poach bird eggs from a nest on some very high voltage power lines using a carbon fiber landscaper grabber tool.
It is not clear as to the fate of the man, and the news lady is totally clueless, but you can see what's left of the pole in her left hand. As she states, it looks like hair or a wig.
Those power lines are part of south Florida's power grid. The other end goes to two power plants about 70 miles to the south. One is nuclear, the other is gas fired, both make LOTS of power. Their red and white stacks were one of several landmarks used by boaters along the south Florida shore line. The water tower that was struck in my shocking moment was another landmark which led me back to my trailer.
South Florida Man Nearly Electrocuted Trying To Reach Bird’s Nest Off Power Line – CBS Miami
Haven’t you ever seen a two-plugged extension cord used to daisy chain two mobile homes before? One with the electricity shut off for non-payment…..
And how hard could it have POSSIBLY been to run a two foot piece of Romex before the sheet rock went up?????
I've seen it going across the hall in an apartment building.
I've been to Jamaica a few times. Stealing electricity there is very common. I've seen jumper wires in the meter box. I've seen automotive jumper cables modified to steal electricity right off the pole.
It's a big problem in India too. Powerless Official Trailer (2014) - Indian Electricity Crisis Documentary HD - YouTube
The three stooges as electricians - YouTube 😀