Most of us have had a close call...what's your worst? I've been fortunate...my biggest shock was around age 12 when I found out the hard way that there really is many kilovolts in those 1960's TV picture tubes. Slammed me against the wall but taught me a healthy respect for HV 2 years before I ever saw the insides of a broadcast transmitter.
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Worst Shock Experience
- Thread starter BobOnTheJob
- Start date
People usually laugh when I say my worst shock was from 6 volts AC. 6 volts at 75 amps 
measuring filament voltage. I Thought the front panel meter was not reading correctly. Checking with a fluke below the tube cavity using two hands like an idiot.......... My arms hurt for a week. I've had a few RF burns also, which are technically shocks, but are much different. Recently I had the opportunity to participate in a law enforcement class on Tasers. I took the ride as they call it. Another dumb decision. ??? It ranks up there with the filament shock.
measuring filament voltage. I Thought the front panel meter was not reading correctly. Checking with a fluke below the tube cavity using two hands like an idiot.......... My arms hurt for a week. I've had a few RF burns also, which are technically shocks, but are much different. Recently I had the opportunity to participate in a law enforcement class on Tasers. I took the ride as they call it. Another dumb decision. ??? It ranks up there with the filament shock.BobOnTheJob said:
Had the picture tube experience at about the same time of my life. But even so I didn't get the message until later about the big electrolytic capacitors used in HV power supplies. Final lesson was on the wisdom of protective grounds when as one of the AV Geeks in High School I had my hand on a mike stand on a dew dampened football field. The amplifier in the press box had no chassis ground to earth. Sometimes one never learns but still lives on, God must look out for the stupid.
I built CB booster amplifiers when I was in High School as my part-time job. We never bothered with bleeder resistors across the voltage doubler due to cost so the caps would hold a charge for quite a while after the amp was turned off. I was working on one on my parents breakfast bar. The bar was pretty high so the stools were tall. I forgot the caps might still have a charge and I reached in to move some wires around and touched the capacitor terminal strip with two fingers while holding onto the chassis with the other. I woke up on the floor with cool chills and a nasty bump on my head from falling off the bar stool. The bump (goose egg) was worse than the shock as it hurt for a few days.
It was about 850 volts for sweep tube plate supply.
That taught me to keep one hand in the pocket and always use a shorting screwdriver to discharge the caps.
One of those episodes one will never forget.
It was about 850 volts for sweep tube plate supply.
That taught me to keep one hand in the pocket and always use a shorting screwdriver to discharge the caps.
One of those episodes one will never forget.
Best I can come up with is just accidentally touching one of the plug prongs while trying to plug something into a standard 120 volt AC outlet. Guess most of us have been there and done that before. It's happened twice in my lifetime. The first time as a kid playing with a string of Christmas lights. I was creating my own "flashing" string of lights by repeatedly plugging and unplugging it from the outlet. The second time it happened was in a church auditorium. I was trying to plug a 16mm film projector into an AC outlet that was located halfway under one of the pews. I couldn't see it very well and accidentally touched the plug prong in the process.
I'm glad to hear you guys have survived your ordeals! I'm not trained to service radio and TV transmitters, so I can only imagine how dangerous that type of workreally is.
R
I'm glad to hear you guys have survived your ordeals! I'm not trained to service radio and TV transmitters, so I can only imagine how dangerous that type of workreally is.
R
Years ago while working on the radio studio located at The Gaylord Opryland Hotel in Nashville Tennessee, I had raised an aluminum extension ladder against the side of the building to access the roof of the studio annex. While I was climbing up the ladder that was beneath one of the guest rooms in the hotel, I looked up and saw a lady standing in the window, drapes open. She did not have anything *on*, A N Y T H I N G!!! Now at that same time, there was a college cheerleader convention going on in the hotel and there were thousands of those young ladies in attendance... NOW as a comparison, what I saw standing in that window was the antithesis of those young cheer leaders! Now Back to the ladder; I quickly turned my head, pretending not to see her looking intently towards the 2-way antenna on the roof of the studio.... I then climbed down the ladder and returned to the studio indeed VERY SHOCKED! I am still to this day unable to erase that image... Even considered seeking workman's comp due to the brain damage I suffered as a result of that SHOCKING incident....BobOnTheJob said:
Wasn't the picture tube that got me but that damn lower voltage higher amp damper tube.
Nailed me through the "insulated" anode cap. Wasn't even touching anlything else!
Thought I was going to die. On the floor. Could not get a breath for a long time.
Then there was one of those days where my back was all out of whack. Couldn't take a deep breath type of mid back pain.
But within a half hour of getting nailed with 120 VAC in one hand and out the other I was nearly pain free!
Have NOT tried that again.
Also learned to use a high wattage resistor to discharge 16 mfd @ 25 kv capacitors even after they were previously discharged only minutes before being removed from the circuit. Blew the end off that screwdriver.
Nailed me through the "insulated" anode cap. Wasn't even touching anlything else!
Thought I was going to die. On the floor. Could not get a breath for a long time.
Then there was one of those days where my back was all out of whack. Couldn't take a deep breath type of mid back pain.
But within a half hour of getting nailed with 120 VAC in one hand and out the other I was nearly pain free!
Have NOT tried that again.
Also learned to use a high wattage resistor to discharge 16 mfd @ 25 kv capacitors even after they were previously discharged only minutes before being removed from the circuit. Blew the end off that screwdriver.
I was convinced that a meter on the face of a shipboard WRT-2 transmitter was incorrect so decided to adjust the needle with a screwdriver. The transmitter was not transmitting, I was standing on a rubber mat on a steel deck and holding the screwdriver in one hand only but.....
As I touched the adjustment screw with the screwdriver it hit me like a lightening bolt - the plastic handle of the screwdriver shattering into hundreds of little pieces and the shaft embedded in the steel door of the parts cabinet behind me. The hair on my arm stayed at attention for months.
As I touched the adjustment screw with the screwdriver it hit me like a lightening bolt - the plastic handle of the screwdriver shattering into hundreds of little pieces and the shaft embedded in the steel door of the parts cabinet behind me. The hair on my arm stayed at attention for months.
My most frightening experience was with a 50kW RCA Ampliphase transmitter in the mid 70s. I was installing the transmitter in Guayaquil, Ecuador. After operating the transmitter for a short period of time, I powered the transmitter down. I opened the front door to the high voltage cabinet and started to reach into the cabinet. The hair on my arm bristled and I withdrew my arm. The high voltage bleeder system had failed to operate.
I never again reached into a transmitter without using a 'Jesus Stick.'
I never again reached into a transmitter without using a 'Jesus Stick.'
I shocked myself jump starting a car with a dead battery. I touched both the + and - ends of the jumper cables together that were plugged into the dead car. There was a spark and I felt a shock. And that was from the dead battery!
I held my hand on a Van De Graaff generator. Didn't feel anything while holding it. Then I touched someone else's skin after that and both of us got a nasty shock.
I hate getting shocks. In the winter I discharge myself by holding my car keys and touching the keys to metal.
I held my hand on a Van De Graaff generator. Didn't feel anything while holding it. Then I touched someone else's skin after that and both of us got a nasty shock.
I hate getting shocks. In the winter I discharge myself by holding my car keys and touching the keys to metal.
My greatest electrical shock came from a vintage 1953 Emerson color TV with a metal picture tube. I was working my first "paid" job at a local TV repair shop. As a Senior in high school, I was wearing my brand new class ring. I should have known better. The boss was out making a service call and I was alone, trying to restore life to this twelve year old TV. In a Eureka moment, I found and replaced the offending components, and the set was now making a color picture!
I'd just set the high voltage to the proper 25,000 volts and went about my business of making some last minute tweaks to the set before shutting it down and putting the chassis back in the cabinet. My hand was about four inches from the heavily insulated CRT shroud when I saw a huge spark jump to my class ring. That is the last thing I remember. When I came to, I was outdoors in the rear parking lot of the shop in my shirt sleeves. It was winter, and it was lightly snowing. I have no idea how I got there. When I got myself back inside the building, I discovered that almost 30 minutes had elapsed. The TV had died from arcing through the hole in the insulation where I got the shock. There was a giant black pitted area on the side of my ring where the arc had hit, and my finger was burned where it came in contact with the ring. I think that was the last day I ever wore it...
From that experience, I learned to never wear any kind of jewelry when working with electricity. Even 12 volts in your car can be very uncomfortable when it heats up your ring to a couple of hundred degrees by becoming a conductor to ground.
I'd just set the high voltage to the proper 25,000 volts and went about my business of making some last minute tweaks to the set before shutting it down and putting the chassis back in the cabinet. My hand was about four inches from the heavily insulated CRT shroud when I saw a huge spark jump to my class ring. That is the last thing I remember. When I came to, I was outdoors in the rear parking lot of the shop in my shirt sleeves. It was winter, and it was lightly snowing. I have no idea how I got there. When I got myself back inside the building, I discovered that almost 30 minutes had elapsed. The TV had died from arcing through the hole in the insulation where I got the shock. There was a giant black pitted area on the side of my ring where the arc had hit, and my finger was burned where it came in contact with the ring. I think that was the last day I ever wore it...
From that experience, I learned to never wear any kind of jewelry when working with electricity. Even 12 volts in your car can be very uncomfortable when it heats up your ring to a couple of hundred degrees by becoming a conductor to ground.
My son sometimes sets up and runs sound for large theatrical shows. After each performance, they change the 9 volt batteries in all the wireless transmitters. In a moment of brilliance, on a dare he decided to snap all the used 9 volts in series and see what kind of shock batteries can produce. He's lucky to be alive because he caught it from hand to hand right across the chest. I calculated >250 volts.
Myself, I was on a pitched metal roof stringing RG-8 coax for a radio RPU setup and leaned over the building's 3 phase service entrance. Over the years the insulating compound on the splices had deteriorated and cracked and I discovered it the hard way. Fortunately I caught myself before I rolled completely off the roof...
Myself, I was on a pitched metal roof stringing RG-8 coax for a radio RPU setup and leaned over the building's 3 phase service entrance. Over the years the insulating compound on the splices had deteriorated and cracked and I discovered it the hard way. Fortunately I caught myself before I rolled completely off the roof...
Caps on a two tube "cb amplifier" I put together using TV sweep tubes as a teenager. Knocked me back across the garage and my arm was numb for a couple of hours.
Made my own "Jesus Stick" for it shortly after that.
Also got a good RF burn at an AM site while taking base current readings. Swarm of hornets came up out of a hole in the cinderblock wall of the tuning house... brushed my hand across the feeder trying to get out of there and wave the hornets off my face.
Made my own "Jesus Stick" for it shortly after that.
Also got a good RF burn at an AM site while taking base current readings. Swarm of hornets came up out of a hole in the cinderblock wall of the tuning house... brushed my hand across the feeder trying to get out of there and wave the hornets off my face.
Back in my high school days we had an auto shop instructor who was a bit of a practical joker. One day, as we were all leaning over the hood of an old '49 Chevy he put his hand on the coil (engine running) then touched one of my classmates on the edge of one of his ears. Friends say you could hear the pop clear across the shop floor. The dent in the fender from the kid's knee is probably still there.
Anyone remember those plastic seat covers for cars in the 50's? My folks had my grandmother's old '39 Chevy which had big couch-like seats and both front and rear had heavy plastic seat covers. My sisters favorite trick was to slide back and forth on the seat then reach up and touch my dad's ear (he would be driving at the time). Usually it was just a little spark and tickle but there was one memorable time when she must have been wearing woolen underware and when she touched his ear the entire interior of the car lit up. He stopped the car and gave my sister the spanking of her life. Last good memory of my sister that I have. ;D
Anyone remember those plastic seat covers for cars in the 50's? My folks had my grandmother's old '39 Chevy which had big couch-like seats and both front and rear had heavy plastic seat covers. My sisters favorite trick was to slide back and forth on the seat then reach up and touch my dad's ear (he would be driving at the time). Usually it was just a little spark and tickle but there was one memorable time when she must have been wearing woolen underware and when she touched his ear the entire interior of the car lit up. He stopped the car and gave my sister the spanking of her life. Last good memory of my sister that I have. ;D
The ol' high school electronics class joke of tossing a charged cap to someone.
;D
;D
I used my teeth to strip wire off a phone line that I had left plugged in and it rang. It's only 105-120 v but it felt a lot worse. I lived aboard a boat that was docked and the stupid cheap extra long marine phone line connector was too easy to break. They have 3 prong weird looking connectors that go into what looks like a European looking "mains" electrical box that was on the dock side.
I've had a few other shocks and frankly I am surprised I haven't been hurt worse especially since I've been a tinkerer since my childhood. knock on wood!
I've had a few other shocks and frankly I am surprised I haven't been hurt worse especially since I've been a tinkerer since my childhood. knock on wood!
A radio colleague and I were at the transmitter site of an AM daytimer. A second station in town had lost their tower site and were diplexing onto ours.
I don't remember the details, but both stations were 5 kw. We signed off at sunset, while the other station stayed on overnights with something like 17 watts.
A group of engineers worked on the diplexing project for days. One afternoon my colleague was right by the tower and both stations were brought up to full power. My friend pulled up a handful of weeds, then went to stand up. His forehead brushed the bottom of that tower. For several weeks afterwards his forehead resembled a waffle iron.
I don't remember the details, but both stations were 5 kw. We signed off at sunset, while the other station stayed on overnights with something like 17 watts.
A group of engineers worked on the diplexing project for days. One afternoon my colleague was right by the tower and both stations were brought up to full power. My friend pulled up a handful of weeds, then went to stand up. His forehead brushed the bottom of that tower. For several weeks afterwards his forehead resembled a waffle iron.
I learned about RF burns while exploring the transmitter site of KDKA-AM 1020 about thirty-five years ago.At that time their AUX antenna was a 300 ohm horizontal dipole constructed on some insanely high utility poles.
The four conductor open feed line was supported on poles that were short enough that the feed lines were within easy reach of the ground,and close enough to the ground that the RF field would kill only certain kinds of plants growing on the ground.
I took note of the open knife switches outside of the fence that surrounded the transmitter building that were used to connect the transmitter to the AUX, or to shunt the dipole to ground.The grounding switch was closed,the feed switch was open but being young and dumb, I just HAD to encircle one of the four feed line conductors with my finger and thumb.
I was rewarded with a loud SNAP!, a flash of sorts and quick numbness of the exposed digits. The smell of unhappy epidermis was apparent but the real pain did not surface until hours later.
Such was my lesson on how a solid appearing mechanical ground may NOT be a good RF ground, and when within a 50 kW RF field emanating from a 718 foot tower,one should probably keep one's hands in their pockets. <VBG>
The four conductor open feed line was supported on poles that were short enough that the feed lines were within easy reach of the ground,and close enough to the ground that the RF field would kill only certain kinds of plants growing on the ground.
I took note of the open knife switches outside of the fence that surrounded the transmitter building that were used to connect the transmitter to the AUX, or to shunt the dipole to ground.The grounding switch was closed,the feed switch was open but being young and dumb, I just HAD to encircle one of the four feed line conductors with my finger and thumb.
I was rewarded with a loud SNAP!, a flash of sorts and quick numbness of the exposed digits. The smell of unhappy epidermis was apparent but the real pain did not surface until hours later.
Such was my lesson on how a solid appearing mechanical ground may NOT be a good RF ground, and when within a 50 kW RF field emanating from a 718 foot tower,one should probably keep one's hands in their pockets. <VBG>
Back in the 90's I opened up the front of a FM20H3 and used the shorting stick like a good little cub. Problem was I forgot to kill the power first. I wasn't hurt (except for having the living Jebus scared out of me) but the stick had what looked like a bite taken out of it. I NEVER forgot that lesson.
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