"A TV question for any pro....before I SERVICE IT!"

[DarkFudge2000]

Folks....I have owned a 32" Sony Trinitron for about 7 years now and the picture has always been fantastic....until today. I turned on my TV and noticed the top portion of the picture pushed down a few inches and above it are 3 very thin horizontal lines , red, blue, green running across right above the pushed down picture. The best way to describe it is...its as if someone adjust the horizontal tracking and slightly pushed the whole image down a bit. Now on these TVs, I dont know if there is a way to simply readjust the image UP. On the OLD TVs you had control of horizontal and vertical adjustments as you do with monitors...but for this TV, what can I do?.....Unless there is some sort of hidden tracking somewhere??

BEfore I spend a fortune to have this fixed could someone lead me in the right direction with what they think it could be...thanks!!!

 

[dkozloski]

The most common source of problems in old TV's and monitors is electrolytic capacitors drying out with the prolonged time and heat. You may be able to adjust it out for a while but the trouble will be back. Todays consumer electronics is a consumable item. We live in a throw away world.

 

[AndyCunningham]

Even in the slow moving world of CRTs, 7 years is a long time, and there's probably much nicer models out now. If you can't fix that TV at a reasonable price just get a new TV. If you've got any options like Zoom modes you might consider that to hopefully push the bands off the top of the TV, although of course then you'll lose even more of the bottom of the picture.

 

[StandardCell]

<< The most common source of problems in old TV's and monitors is electrolytic capacitors drying out with the prolonged time and heat. You may be able to adjust it out for a while but the trouble will be back. Todays consumer electronics is a consumable item. We live in a throw away world. >>



I second this one. My dad fixed a friend's monitor a couple of months ago with this exact problem. Don't ask me which cap or where, but be warned - VERY dangerous voltages exist inside a tv, even while off.

 

[Bozz]

560mF/50V capacitor in the middle of the circuit board, next to a heatsink for the vertical output IC. It controls the vertical linearity output S shaping circuit.

Go ahead, open the TV and risk killing yourself by electrocution and/or by flinching when a charged component causes your arm/body part to jerk causing you to break the neck of the CRT resulting in glass flying at high velocity, only idiots ignore the warnings about there being no user serviceable parts inside a high voltage device.

I am a qualified service technician, I know the fault well, if you are not fully competant with television electronics then give it to a professional.

Oh, and Sony TV's do not expire in 7 years, cheap brand ones do. A Sony television could damn well last 20 years. Yeah lets ignore a job that a pro would charge between $45-90 and lets buy a new $1000 Sony television because I am going to notice the 5% picture quality improvement. Same goes with cars, scrap the piece of junk old car that's made of metal and buy a new Hyundai plastic fantastic, gotta be better!

(/sarcasm mode off)

 

[Mday]

i agree with the warnings (death and ability)... if you are handy with electronics, i mean hardcore, by all means.

otherwise, get it repaired (estimates first) and check for qualitifications and recommendations.

--

my 12 year old sony trinitron had 1 problem, external magnetic field caused its electron gun to go wonky. fixed that problem with a degaussing coil. i just have one other problem... i dont have the original remote =\

anyway, it works =D

 

[sharkeeper]

A Must Read!

As for there being "dangerous" voltages present in a TV, I don't think they are life threatening. Yes, the shock is painful and most people will jump and hurt themselves. A microwave oven has voltage (and most importantly--CURRENT!) that will kill you instantly! 2,000 volts with 500 milliamperes is very lethal. Can you say kitchen electric chair??? :Q

Cheers!

 

[Bozz]

<< A Must Read!

As for there being "dangerous" voltages present in a TV, I don't think they are life threatening. Yes, the shock is painful and most people will jump and hurt themselves. A microwave oven has voltage (and most importantly--CURRENT!) that will kill you instantly! 2,000 volts with 500 milliamperes is very lethal. Can you say kitchen electric chair??? :Q

Cheers! >>



As to the comment of non life threatening voltages inside a television, the simplest word to state for that comment is FOOL

You obviously know enough to open a television up and repair it. Go ahead, rid yourself from the gene pool. Dont encourage others to do it however.

I dont mean to sound harsh but a person without any electronics knowledge, let alone being an expert with televisions, can only be described as a silly and stupid moron if he/she opens up a television and starts probing around.

 

[cyclones]

I fully agree with "Bozz" that if you do not have any training in high voltage CRT assembly......."KEEP OUT".
Some of the capacitors in circuits can retain a very large proportion of their charge for a very long time.
To ensure that the correct part is fitted, a bill from an expert with a gaurantee alongside is worth it for a good
piece of equiptment like yours.

 

[Arthalion]

I may be a n00b here, but after reading this thread I just have to throw my 2 pence in before someone does something stupid.

Sharkeeper~ My grandfather was a television repairman who ran his own repair shop from the early 1950's up until his death a few years back. In the late 1980's my grandfather, with 35+ years of experience and a whole wall full of certifications, accidentally struck a capacitor in a console TV with his hand and took a full hit. The jolt, as it passed through his body, stopped his heart dead in his chest and effectively killed him. He ONLY survived because his store was located two buildings down from a fire station, and one of his quick thinking employees ran over and grabbed the rescue team himself rather than waiting for 911. They took the paddles to him and, with one jolt, restarted his heart.

Too many computer guys today refuse to appreciate the power of a large capacitor. A lot of you have been nailed by the weak ones in your computer power supplies, shake off the tingle, and ASSUME that they're all that weak. Let me tell you that I spent MANY of my youthful summers working in my grandfathers shop and I repaired hundreds of televisions ranging from (then) new solid state and projection TV's to ancient tube consoles. Even with that training and experience I WILL NOT open a television today without the proper tools, grounding straps, discharge equipment, and service guides. When my Wega lost VHold a few months back, I didn't even take the back off. I called up a service tech and had it checked professionally.

Anyone who opens a television set without knowing EXACTLY what they are doing is a suicidal FOOL.

 

[Bozz]

Spot on, Arthalion

I dont care if some clueless and mindless twit opens the set up and kills/injures him/herself but advising someone else to do something life threatening is pathetic.

 

[dude]

I remember making a NICE 1 1/2 to 2 inch ARCH with a Fluke on a Monitor.

It made the hairs on our arms stand up just from standing nearby.

 

[sharkeeper]

<< I dont care if some clueless and mindless twit opens the set up and kills/injures him/herself but advising someone else to do something life threatening is pathetic. >>



I always advise people to read the excellent link supplied by electronics guru Samuel Goldwasser. Hopefully the information they would get there would either educate them enough to safely takle it themselves or scare them into taking it to a qualified person!

I would never advise someone with little or no electronics knowledge to do such a thing. An inexperienced person has no business "probing around" the innards of a tv set, Period.

The one appliance that is as common as a tv set that has fatal voltages that *will* kill anyone DEAD is the microwave oven! I wouldn't recommend ANYONE opening one up especially if they intend to run it with the cover off!!! :Q

Cheers!

 

[Bozz]

<<

<< I dont care if some clueless and mindless twit opens the set up and kills/injures him/herself but advising someone else to do something life threatening is pathetic. >>



I always advise people to read the excellent link supplied by electronics guru Samuel Goldwasser. Hopefully the information they would get there would either educate them enough to safely takle it themselves or scare them into taking it to a qualified person!

I would never advise someone with little or no electronics knowledge to do such a thing. An inexperienced person has no business "probing around" the innards of a tv set, Period.

The one appliance that is as common as a tv set that has fatal voltages that *will* kill anyone DEAD is the microwave oven! I wouldn't recommend ANYONE opening one up especially if they intend to run it with the cover off!!! :Q

Cheers! >>



I would not advise anyone to even open up a VCR which often contains a power supply inside a shielded aluminium casing out of reach. Samuel has good experience in the field of repair but a beginner simply should NOT be opening up a video, let alone a television! Besides what the heck could a beginner possibly figure out after opening it up? Could a beginner tell me Ohms law? Could a beginner tell me how the PN junctions in diodes and transistors work and how they react to different voltages and currents? Could a beginner tell me the angular relationship between voltage and current in capacitive and inductive circuits? I could go on for hours, even days.

Put simply only a stupid idiot will open up a high voltage device without knowing exactly how the product works, let alone know basic electronics which is required to know before even attempting to understand theory of operation of the particular product in question. Your statement holds no merit whatsoever. Most current model VCRs have the full mains voltage exposed on the main board as most of them use a single board construction to keep costs down. While you aren't likely to get killed by flying shards of glass from an imploding picture tube, the risk of electrocution is still ever present. This fact applies to computer power supplies as well. Point being even a car amplifier can have enough voltage in it to kill you, many amplifiers that can supply over 100W RMS into a 4 ohm load will have power supplies that have more than +-45 volts on the secondaries, that's over 90 volts of potential.

Electronics is a specialised industry, there are no problems with beginners mucking around with batteries, DC power supplies and low voltage electronics kits, that's how I started learning electronics. Point is, before you even consider tampering with high voltage, at least understand basic electronics, which is around 6 months study, 8 hours a day, 5 days a week. It is NOT something you can learn reading books in bed for 2 hours a night for a week or two.

 

[Bozz]

One other thing, I am a qualified electronics technician (in case you didnt figure that out ), it is all too common for a home user to take a device apart and damage parts of the product. I would have to say this is about 90% of the case. So 9 out of 10 jobs that arrive for repair that the customer has tampered with will end up costing the customer MORE for the service technician to not only fix the original problem but also the extra problems the nosey customer has created.

 

[sharkeeper]

<< Point being even a car amplifier can have enough voltage in it to kill you, many amplifiers that can supply over 100W RMS into a 4 ohm load will have power supplies that have more than +-45 volts on the secondaries, that's over 90 volts of potential. >>



The resistance of the human body is well over 4 ohms. To get resistance low enough for that to be felt would require a lot of sweat. That said, a car battery that can crank out well over 600 amperes could kill a person instantly. Fortunately, people's skin is a good insulator at 12V!

Many factors come into play when dealing with the physiological effects of electrical currents to the human body. Many people have different tolerances to shock as well. Current kills, not voltage. Plain and simple. The reason why higher voltages are assumed to be dangerous is because much more current *can* flow [assuming it's available] if the body contacts these points. The acceleration voltage in some sets is higher than 30kV which is over twice that of common 13.8 kV switchgear that I used to service and maintain. Of course one needs to respect both, but contact with live switchgear only happens once in a lifetime! Something that always gets treated with respect!


Cheers!

 

[Bozz]

Sharkeeper: No television is setup to have a final grid voltage of more than about 28kv simply because exceeding that creates excessivly high emissions of X-rays from the front of the tube. Furthermore it can cause arcing inside the tube.

A lot of cheap televisions have bad power supplies that increase in voltage over time as the electrolytics dry out, and they dont have any form of regulation in the horizontal circuits to regulate the final grid (aquadag or g4 (acceleration voltage is usually 300-600 volts, being g2 or the screen adjustment unless they call they call the final grid the accelration grid in the states..?)) and the voltage goes well above 30kv resulting in very dangerous amounts of Xray radiation leaving the front of the screen. Buying a good brand television has health benefits as well, bet nobody here knew that

One more thing, dry skin typically has a breakover voltage of about 50-70 volts depending on the person. Wet your finger and put a 9 volt square type battery on the wet part. Feel the pain as the current goes through your finger? If your slightly perspiring on your hands as many people do, it merely needs 35-40 volts to break through. Most car amplifiers have around 50-100 volts from the DC-DC converter used inside them. This has NOTHING to do with the 12v from the car battery, that is relatively harmless even if your skin is wet. Without even taking anything apart, turn your car stereo's volume up and put your thumb and forefinger across the speaker and you will feel quite a lot of electricity going through your hand, it will be painful. That is my point, even a benign item such as a car audio amplifier can kill, by what you posted shows you do not have a full understanding of how to develop power. You need voltage which delivers a current depending on the targets impedance. Power equals voltage squared divided by impedance so 12 volts equals 144 / 4 = 36 watts. That is a DC formula but it partially applies. In reality you will not get more than about 20 watts RMS from a 12 volt source by using a twin inverted phase amplifier due to transistor voltage drops.

Cheers

 

[Jerboy]

<< i agree with the warnings (death and ability)... if you are handy with electronics, i mean hardcore, by all means.

otherwise, get it repaired (estimates first) and check for qualitifications and recommendations.

--

my 12 year old sony trinitron had 1 problem, external magnetic field caused its electron gun to go wonky. fixed that problem with a degaussing coil. i just have one other problem... i dont have the original remote =\

anyway, it works =D >>




Monster capacitors have quite some jolt. I haven't played with capacitors in a long time until today. You guys reminded me of all the fun I had with capacitors and I just had to do it.

I charged up a capacitor bank that sums to 6,000µF, 400V DC which holds 480joules. Enough to light up a 100W light bulb for 4.8 seconds. I captured it on video and it didn't capture worth a crap. When you look at it in person, it sounds like a gun shot and flash is absolutely blinding, but it occurs so quickly that CCD couldn't capture it. This tells us that it has enough surge output to drain out enough energy to keep up 100W light bulb for 4.8seconds in a few hundredths of a second. Imagine what this will do to your body!

I also played around with a 40,000V 2µF oil cap and this thing is so amazing and at this voltage and ability to provide 1000's of amps for instantaneous moment, it can easily kill you.

 

[sharkeeper]

<< A lot of cheap televisions have bad power supplies that increase in voltage over time as the electrolytics dry out, and they dont have any form of regulation in the horizontal circuits to regulate the final grid (aquadag or g4 (acceleration voltage is usually 300-600 volts, being g2 or the screen adjustment unless they call they call the final grid the accelration grid in the states..?)) and the voltage goes well above 30kv resulting in very dangerous amounts of Xray radiation leaving the front of the screen. Buying a good brand television has health benefits as well, bet nobody here knew that >>



Don't most sets have a safety gap that will discharge in event of extreme over voltage?



<< One more thing, dry skin typically has a breakover voltage of about 50-70 volts depending on the person. Wet your finger and put a 9 volt square type battery on the wet part. Feel the pain as the current goes through your finger? If your slightly perspiring on your hands as many people do, it merely needs 35-40 volts to break through. Most car amplifiers have around 50-100 volts from the DC-DC converter used inside them. This has NOTHING to do with the 12v from the car battery, that is relatively harmless even if your skin is wet. Without even taking anything apart, turn your car stereo's volume up and put your thumb and forefinger across the speaker and you will feel quite a lot of electricity going through your hand, it will be painful. That is my point, even a benign item such as a car audio amplifier can kill, by what you posted shows you do not have a full understanding of how to develop power. You need voltage which delivers a current depending on the targets impedance. Power equals voltage squared divided by impedance so 12 volts equals 144 / 4 = 36 watts. That is a DC formula but it partially applies. In reality you will not get more than about 20 watts RMS from a 12 volt source by using a twin inverted phase amplifier due to transistor voltage drops. >>



I have plenty of background and experience on "developing power". My analogy comparing things to a car battery was misunderstood. The point was that you can have plenty of current but as long as there isn't enough voltage to allow it to flow, you're safe.

What can give a hazardous shock that most people here have is a UPS. Most use low voltage lead acid piles usually 6 or 12 volts. Yet they can put out 120 volts of something that resembles sinus power. The better ones actually do put out sinus power. Ones like I've serviced that have 196 volt battery arrays (4500 A/H) and large ferroresonant tranformers weighing a few tons!

Anyway, my threshold for feeling pain is very high. I've never been able to feel the tingle from a nine volt pile with the exception of putting the terminals on my tongue! My 11W RMS Delco head unit in my car would never develop enough open circuit volts to be felt on my hand. My Mark Levinson No. 33H power amp that I use at home can make a strong shock similar to an encounter with primary house current, however.

Probably the best example of using a very safe source (9V pile) into something that can be unpleasant is a handheld "stun gun" carried by some law enforcement personell. The 100,000V or so these units claim to put out sounds very intimidating, and the feeble current (60 microamperes) certainly WILL flow through one's body regardless of their condition! They certainly won't kill anyone, just cause muscle contractions. People like me just get pissed off. My wife bought one for "personal protection" and she was scared sh!tless when I shocked myself with it and said that would just make me more pissed off! Now if someone came after me with a nice 20kV 15mA power brick, I'd run if I didn't have a piece!

Cheers!

 

[sharkeeper]

<< I charged up a capacitor bank that sums to 6,000µF, 400V DC which holds 480joules. Enough to light up a 100W light bulb for 4.8 seconds. I captured it on video and it didn't capture worth a crap. When you look at it in person, it sounds like a gun shot and flash is absolutely blinding, but it occurs so quickly that CCD couldn't capture it. This tells us that it has enough surge output to drain out enough energy to keep up 100W light bulb for 4.8seconds in a few hundredths of a second. Imagine what this will do to your body! >>



Capacitor banks are very dangerous! When you get over half a kV with a few hundered mfd, the traumatic damage they can inflict is rather high. Being a low impedance device, once a cap finds a discharge path, the discharge occurs quickly. (upon breakdown)

Cheers!

 

[cyclones]

On the basis that this thread will run and run.......
Aside from everyday household electrical items like stun guns and laser beam destroyers,
great care should be taken when dismantling Dilithium Crystals Power Supplies in space ships.
I saw a very nasty incident some years ago when Engineering Officer Scottie and Captain Kirk ...eeeeeh!

 

[Bozz]

<< Don't most sets have a safety gap that will discharge in event of extreme over voltage? >>



Not for the 26KV (EHT) line. Most televisions have a spark gap built into the CRT socket for G3 (Focus) and some also have a spark gap for G2 (Screen, or Accelerating grid). Usually if the EHT rises so will the G2 and G3 voltages and trigger the spark gap. But by this time the EHT will be well into the 35kv or higher region which commonly destroys a picture tube by puncturing a pinhole on the neck of the CRT and allowing (1) the EHT to arc, possibly blowing up the horizontal output transistor and (2) air to be slowly sucked into the CRT destroying it over a period of a few hours up to a few months.



<< I have plenty of background and experience on "developing power". My analogy comparing things to a car battery was misunderstood. The point was that you can have plenty of current but as long as there isn't enough voltage to allow it to flow, you're safe. >>



Spot on! My point was that a simple device such as an audio amplifier for a car indeed does generate sufficient voltage to pose an electrocution risk.



<< What can give a hazardous shock that most people here have is a UPS. Most use low voltage lead acid piles usually 6 or 12 volts. Yet they can put out 120 volts of something that resembles sinus power. The better ones actually do put out sinus power. Ones like I've serviced that have 196 volt battery arrays (4500 A/H) and large ferroresonant tranformers weighing a few tons! >>



Yep, in fact some UPS's have mains voltage potential on the battery, if you leave it plugged in while you attempt to change the battery (dont forget almost universally the case is earthed) then you may not live to tell about your ordeal.

Anyway, my threshold for feeling pain is very high. I've never been able to feel the tingle from a nine volt pile with the exception of putting the terminals on my tongue! My 11W RMS Delco head unit in my car would never develop enough open circuit volts to be felt on my hand. My Mark Levinson No. 33H power amp that I use at home can make a strong shock similar to an encounter with primary house current, however.

Probably the best example of using a very safe source (9V pile) into something that can be unpleasant is a handheld "stun gun" carried by some law enforcement personell. The 100,000V or so these units claim to put out sounds very intimidating, and the feeble current (60 microamperes) certainly WILL flow through one's body regardless of their condition! They certainly won't kill anyone, just cause muscle contractions. People like me just get pissed off. My wife bought one for "personal protection" and she was scared sh!tless when I shocked myself with it and said that would just make me more pissed off! Now if someone came after me with a nice 20kV 15mA power brick, I'd run if I didn't have a piece!

Cheers![/i] >>



Dont you need around 2mA to feel electricity flowing through your body? I'm not 100% on this so pls correct me if I'm wrong. 60uA (or 0.06mA) would not be felt..?? But like you said, 15mA of current through your body would not be a pleasant feeling

 

[Jerboy]

<<

Anyway, my threshold for feeling pain is very high. I've never been able to feel the tingle from a nine volt pile with the exception of putting the terminals on my tongue! My 11W RMS Delco head unit in my car would never develop enough open circuit volts to be felt on my hand. My Mark Levinson No. 33H power amp that I use at home can make a strong shock similar to an encounter with primary house current, however.

Probably the best example of using a very safe source (9V pile) into something that can be unpleasant is a handheld "stun gun" carried by some law enforcement personell. The 100,000V or so these units claim to put out sounds very intimidating, and the feeble current (60 microamperes) certainly WILL flow through one's body regardless of their condition! They certainly won't kill anyone, just cause muscle contractions. People like me just get pissed off. My wife bought one for "personal protection" and she was scared sh!tless when I shocked myself with it and said that would just make me more pissed off! Now if someone came after me with a nice 20kV 15mA power brick, I'd run if I didn't have a piece! >>



I have a relatively high pain of threshold too. Capacitors are unlike most high votlage power supplies that can only supply very low current and usually inversely proportional to voltage and current limited by output impedence. Capacitors have very low impedence and current is limited by our body resistance. When we are talking about shocks from capacitor, it usually means higher the voltage, greater the current. Capacitors don't have whole alot of energy, but discharge some serious power for very very short moment, a worst nightmare for hearbeat.

Oil capacitors have even lower impedence than electrolytic and large oil filled capacitors are lethal. This is the type found in a microwave oven and some RF communication equipments.

I got shocked by this beast not that long ago. I was in different world when I realized my whole perception was warped and in fuzzy. I thought I died. When my sense finally got back to nomal, ten minutes had passed. That capacitor is rated at 5,000V 2µF, but I had it charged to 6,000V when I accidentally let it discharge into my body. I was working with something hooked up to one terminal when my other hand got too close to the other terminal. Next thing I knew was I was in a different world for ten minutes. I feel very lucky that I survived. The capacitor held 36 joules. Imagine what would have happened to me had I been messing with my 40,000V 4µF(f'in huge and heavy) 3.2kJ cap.

Word of advise: Leave the caps and appliances containing them alone.

 

[sharkeeper]

<< Yep, in fact some UPS's have mains voltage potential on the battery, if you leave it plugged in while you attempt to change the battery (dont forget almost universally the case is earthed) then you may not live to tell about your ordeal. >>



Some poorly designed UPS' also will spill 120VAC through the power cord when running on batteries! When the power fails and your UPS is plugged in, the resistance on the utility side is the site wiring plus the secondary in the mains transformer. (pole pig) If you unplug the UPS to test it and it's a poor design, you can actually get shocked by touching the plug prongs! YIKE! :Q



<< Dont you need around 2mA to feel electricity flowing through your body? I'm not 100% on this so pls correct me if I'm wrong. 60uA (or 0.06mA) would not be felt..?? But like you said, 15mA of current through your body would not be a pleasant feeling >>



Yes this is true for CW power. The averaged CW power of the stun guns is in the 60~100 microampere range. The current is pulsed quite strongly which creates the actual discomfort. The pulse is also at a timing that *shouldn't* cause life threatening cardiovascular reaction! Note that most people that these stun guns would be used on wouldn't have weak hearts but hey in 2002 you never know!



<< I got shocked by this beast not that long ago. I was in different world when I realized my whole perception was warped and in fuzzy. I thought I died. When my sense finally got back to nomal, ten minutes had passed. That capacitor is rated at 5,000V 2µF, but I had it charged to 6,000V when I accidentally let it discharge into my body. I was working with something hooked up to one terminal when my other hand got too close to the other terminal. Next thing I knew was I was in a different world for ten minutes. I feel very lucky that I survived. The capacitor held 36 joules. Imagine what would have happened to me had I been messing with my 40,000V 4µF(f'in huge and heavy) 3.2kJ cap.

Word of advise: Leave the caps and appliances containing them alone. >>



I'd say it was just a matter of timing that could've easily saved your life. A strong jolt delivered in phase with the heart's timing has a much greater chance of stopping it, even with much lower potential.

Caps are neat devices. There are also quite a few devices in our scientfic community (such as flashlamp pumped solid state lasers and x-ray machines) that use extremely dangerous power supplies.

You can make yourself part of a large capacitor that can startle the bejesus out of yourself and others! All is needed is a CRT TV set (25" works really well) and a really dry day. While wearing rubber soled shoes, either turn on the set (or if it has been playing turn it off) and run your hand all around the CRT face. Keep your hand about 1/4 inch from the glass. All that popping you hear is actually sparks jumping (you can see them at night with your eyes adjusted) to your skin. This will raise your potential to impressive levels! (electrical wise) If the air is really dry you can walk around for up to a minute and still have enough charge to give someone a very uncomfortable shock! If the humidity is over 40% you'll need to move very quickly because the potential will leak due to the moisture in the air. Touching a metallic grounded object will produce the greatest (rapid) discharge that is often very unconfortable. If you don't enjoy shocks (or are afraid of touching a doorknob after walking across the carpet) I don't recommend this!

Cheers!

 

[Jerboy]

<< You can make yourself part of a large capacitor that can startle the bejesus out of yourself and others! All is needed is a CRT TV set (25" works really well) and a really dry day. While wearing rubber soled shoes, either turn on the set (or if it has been playing turn it off) and run your hand all around the CRT face. Keep your hand about 1/4 inch from the glass. All that popping you hear is actually sparks jumping (you can see them at night with your eyes adjusted) to your skin. This will raise your potential to impressive levels! >>



Enough to black you out for a few sec and leave your arm painful for a few hours?

When I got shocked from that capacitor, it sound like a toy "cap gun". I think I can tolerate it again, except that it has too much chance of damaging my body physically. All 36joules of energy discharged into me in milliseconds. Let's assume 5ms. That made my entire body a nice 7.2KW heater for 0.005sec.