At 10:45 AM 3/8/2013, Alistair Bell wrote:
>Mehdi Sadaghdar must be responsible for thousands of coffee spit
>takes. His latest "tutorial" vid is about the question; what hurts
>most? AC or DC?

Wow!  The man is a glutton for pain. Not just in that video, in all
of them.  Is he a Vancouver local?  What's his day job?

 From my own experience of a misspent life his results are about
right, but I wouldn't willingly go as high as 9 VDC continuous, just
a quick dab.   But he's willing to stick 25 VDC on his tongue and
pretend it was an accident.

He took some "static" over at EE (Electronic Engineering) Times over
his ESD demonstration video, see
http://www.eetimes.com/electronics-blogs/other/4404785/How-NOT-to-make-a-training-video
, and he responds in the comments.  I think he glosses over (by
implication anyway) how dangerous some of the stuff in those videos
really is.  The high-current stuff, not the high-voltage. What he's
doing to his tongue isn't dangerous -- unless he lets those power
supply terminals touch each other.  But when he starts swinging
wrenches around car batteries it's a different story, as is any high
voltage that has a capacitor associated with it.

I wonder how much prep/calibration/persistence/blind luck it took to
get the cap in the blinker circuit to blow off at the right
moment.  Back at Analogic, in the Bad Old Days before they started
embossing the tops of electrolytic caps so they'd peel open instead
of blow the can off, every once in a while someone would
intentionally or otherwise install one of the big caps in backwards
in the remote weighing device (universal load cell amplifier/readout,
eight digits or better IIRC) my group was building on the swing shift
in the otherwise deserted Data Precision factory in Danvers
Massachusetts (D-P only ran one shift).  A while later everyone would
jump -- we'd hear a Pop-CLANG from the burn-in line as the can went
rocketing away and bounced off the steel roof, and the offending
system would have a bird's nest of capacitor innards littering the case.

Gee...Eudora thinks I should have my keyboard washed out with soap
because I said "his tongue" twice. That caught me by
surprise.  Eudora has an even saucier mind than I do.  Perhaps if I
said "his lingual member"?  Yup, that's completely inoffensive and
not subject to misinterpretation.  Uh huh...

Yrs,
d