Electric Shock

[Harry Bloomfield Esq]

The Natural Philosopher has brought this to us :

What, the final statement about the muscles expanding? In that case yes..

[Jim Stewart ...]

DC will kill an Elephant...tee hee

[Animal]

and that currently there is no voltage

[Animal]

Do you mean early BWs? I don't know of any colour sets with mains transformer EHT supply.

[Max Demian]

I thought the main remedy was just to put a large value resistor in series with the EHT so the voltage would drop if you touched it, and insulate the direct connections to the EHT.

Didn't they always derive the EHT from the LOPT, even when they had transformers, double wound or auto for the other supplies?

[The Natural Philosopher]

Oh dear.

Actually a current DOES flow in a superconductor all by itself.

Just takes a magnetic field, which has no EMF

Your understanding is shot. Voltage doesn't cause current, current causes voltage. V=IR. If no R, then no V.

[The Natural Philosopher]

Basically yes, muscles relax when the EMF drops to zero - with AC that happens, with DC it doesn't. Reverse polarity is meaningless

[Andrew]

Does the US electric chair use AC or DC ? Often wondered.

[Fredxx]

And is this magnetic field just magicked out of thin air?

Your understanding is shot. You are no engineer. If you were you would understand there is a strict relationship between the two. They are reliant on each other, with very few exceptions.

[Scott]

Didn't Edison and Tesla conduct experiments electrocuting dogs to show that one or other current was more dangerous?

[Robin]

On the other hand [sic] the frequency of "mains" AC is bang in the range that causes muscle tetany

[Andy Burns]

[The Natural Philosopher]

yup. Or out of a permanent magnet

LoL. you don't know the half of it.,

I bet you didn't even do A level physics

[Max Demian]

Edison said AC, to persuade people to opt for his "less dangerous" DC system.

[newshound]

He tried to get people to use the term "Westinghoused" for the process :-)

[newshound]

No. My understanding is that the voltage was significantly higher in the first colour TVs.

My BIL is a baby boomer, B&W tvs took off in the UK with the Coronation in 1952.

[newshound]

George Orwell has a very honest essay about his difficulties when required to shoot a rogue elephant in Burma.

(It's also something of a metaphor for colonialism, but the narrative is quite distressing).

[Jon]

Even in black and white projection sets, using the Mullard MW62 tube required a 30kV flyback transformer.

[John Walliker]

It does take a significant voltage to drive current into a large superconducting magnet in a reasonable time due to its inductance. A whole body MRI scanner magnet will have an inductance of about 40H. The current in the windings will be several hundred amps. So with a 5V power supply it will take an hour to build up a current of 450A in the magnet windings.

John

[newshound]

I can't cite a source, but I am pretty sure there was a spike in repair person fatalities with early colour TVs. I *thought* the voltage was higher, but maybe it was the current (or perhaps both). Or maybe early colour TVs were also less reliable than B&W of the same time.

I'll ask BIL next time I see him. I've forgotten the details of how CRT TVs worked.

I do remember our first B&W TV having to go back to the shop regularly. A Peto Scott, istr. Later ones from Radio Rentals were much more reliable.