On Friday, March 8, 2013, David Beierl wrote:

> 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<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
>