whitequark has quit [Remote host closed the connection]
whitequark has joined #qi-hardware
aazzddgg has quit [Quit: Leaving]
wej has quit [Ping timeout: 252 seconds]
dos11 has quit [Ping timeout: 252 seconds]
wej has joined #qi-hardware
atommann has joined #qi-hardware
nicksydney_ has joined #qi-hardware
nicksydney has quit [Remote host closed the connection]
nicksydney_ has quit [Remote host closed the connection]
nicksydney has joined #qi-hardware
xiangfu has joined #qi-hardware
wej has quit [Ping timeout: 260 seconds]
atommann_ has joined #qi-hardware
atommann has quit [Ping timeout: 264 seconds]
wej has joined #qi-hardware
jekhor has joined #qi-hardware
pcercuei has joined #qi-hardware
sb0 has joined #qi-hardware
jekhor has quit [Ping timeout: 252 seconds]
jekhor has joined #qi-hardware
jekhor has quit [Ping timeout: 240 seconds]
jekhor has joined #qi-hardware
jekhor has quit [Ping timeout: 265 seconds]
wolfspraul has joined #qi-hardware
jekhor has joined #qi-hardware
rz2k has joined #qi-hardware
xiangfu has quit [Remote host closed the connection]
jekhor has quit [Ping timeout: 276 seconds]
atommann_ has quit [Quit: Leaving]
dandon has quit [Quit: .]
dandon has joined #qi-hardware
dos11 has joined #qi-hardware
jekhor has joined #qi-hardware
wej has quit [Ping timeout: 260 seconds]
atommann has joined #qi-hardware
Luke-Jr has quit [Remote host closed the connection]
Luke-Jr has joined #qi-hardware
dos11 is now known as dos1
nicksydney has quit [Ping timeout: 264 seconds]
atommann has quit [Quit: Leaving]
wej has joined #qi-hardware
jekhor has quit [Read error: Operation timed out]
FDCX has quit [Remote host closed the connection]
FDCX has joined #qi-hardware
sb0 has quit [Ping timeout: 252 seconds]
atommann has joined #qi-hardware
rz2k has quit []
sb0 has joined #qi-hardware
arielenter has joined #qi-hardware
pcercuei has quit [Ping timeout: 276 seconds]
pcercuei has joined #qi-hardware
atommann has quit [Quit: Leaving]
<wpwrak>
DocScrutinizer05: i have a little "electronics vs. the human body" puzzle. let's assume you wanted to build a wrist watch like device whose principal function was to alert you of something, e.g., like an alarm clock.
<wpwrak>
now, the signal the device produces should be completely unnoticeable to others. so no buzzing or beeping, no flashing light, and also a vibration alarm may be a bit too intrusive
<larsc>
I guess that rules out high voltage shocks as well
<wpwrak>
i was thinking that one could perhaps use a mild electric shock, just across the wrist. do you think that would work well ? the shock should just be strong enough that one notices, not strong enough to cause involuntary muscle contraction or such
<DocScrutinizer05>
adjustable 100..10000V spikes. Possibly energy-defined, not voltage-defined
<wpwrak>
can't that work with less ?
<DocScrutinizer05>
less than 100V are hardly noticeable
<wpwrak>
10 kV would arc ;-)
<DocScrutinizer05>
use a multiplier and adjust the frequency. It will nicely attenuate voltage with increasing load
<DocScrutinizer05>
use sufficiently large electrodes
<wpwrak>
what would be the easiest way to produce such a 100 V charge ?
<DocScrutinizer05>
but not too large since that increases the power you need to apply
<DocScrutinizer05>
multiplier, as I said. Or boost converter
<DocScrutinizer05>
prolly both
<wpwrak>
(electrode size) well, the whole thing should be wrist watch sized
<DocScrutinizer05>
boost plus 4* multiplier
<wpwrak>
ah, boost plus diode "ladder"
<DocScrutinizer05>
yeah, I *guess* 1..2 cm^2 per electrode (with one electrode as well could be much larger) should work
<DocScrutinizer05>
yes, ladder == multiplier
<DocScrutinizer05>
though ideally you use AC
<DocScrutinizer05>
less electrolytic wear of electrodes
<DocScrutinizer05>
but AC needs to be <500Hz to avoid skin effect
<wpwrak>
wear is probably not a big issue since it would have a very low duty cycle
<DocScrutinizer05>
:nod:
<DocScrutinizer05>
try a boost converter with high voltage switch (GTA or sth)
<wpwrak>
GTA ?
<DocScrutinizer05>
don't forget OV-protection, so it doesn't fry your circuit when the clock has no 'load'
<DocScrutinizer05>
GTO
<wpwrak>
still don't know what the acronym means :)
<DocScrutinizer05>
e.g. there's zilch measures to adjust the power
<DocScrutinizer05>
suuure >> WARNING: This can Kill Smaller animals, such as cats and rabbits, And Probably Even Small Children!<<< *exactly* what you need
<DocScrutinizer05>
duration you open up the IGBT determines the amount of energy stored in choke - or in your device as thermal energy when you open up too long
<DocScrutinizer05>
IGBT breaking the current will cause the energy in choke to go via electrode, whatever it takes to do that
<DocScrutinizer05>
unless the Zener kicks in, so you *really* need the Zener when your device fires with electrode NC
<DocScrutinizer05>
I can't think of a simpler (and worse designed) circuit
<DocScrutinizer05>
you at least should make sure that your MCU can't open the IGBT permanently
<DocScrutinizer05>
use a capacitor to couple the gate/basis to GPIO
<DocScrutinizer05>
this will limit the open-time to at least something
<wpwrak>
and yes, the basic concept always seems the same
<DocScrutinizer05>
you might want to conect electrode1 via a capacitor to choke*IGBT
<DocScrutinizer05>
to stop any current created from electrolytic of electrodes on wet skin
<wpwrak>
ah, i see
<wpwrak>
okay, i think i have enough i to process at the moment :) (still a bit hung over from the weekend) thanks a lot !
<DocScrutinizer05>
yw
<DocScrutinizer05>
can I have one of those? I'm pondering exactly same since years
<DocScrutinizer05>
wrist watch without display
<DocScrutinizer05>
still you always know the time exact to the minute
<wpwrak>
heh, need to see where that goes. a friend asked me if something with a vibration alarm could be built. it wouldn't actually be used as what we'd normally consider an "alarm" but rather to randomly interrupt the person wearing the device, which supposedly would help to enhance the person's ability to pay attention
<wpwrak>
i fear the rationale behind that claim may reside deep in the metaphysical, though :)
<whitequark>
I would find whoever made that device and strangle them in their sleep
<wpwrak>
"what time is it ?" "it's just been three jolts."
<wpwrak>
whitequark: that was roughly my reaction as well ;-)
<DocScrutinizer05>
three jolts sounds like dyscordian