<whitequark>
meh. just don't let it heat up too much
<whitequark>
I'm sure overheated PCB, components, plastics, etc, etc release not less harmful chemicals
<whitequark>
*rereads* though I think I'll make a fume hood for that
<DocScrutinizer05>
I ponder to build modified deep friers (with emergency cut out at 260°C by dedicated thermofuse) with thermostat replaced by special thermo regulation (processor based?) that also uses additional sensors to detect vapor level in tub, then add some Galden in a bottle to the kit and sell it as convenience-package
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<DocScrutinizer05>
actually, it's hard to come up with a good story how considerable amounts of a fluid that evaporates at 200 or 230°C can get heated up to a temperature of 290°C so it decomposes into toxic stuff
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<DocScrutinizer05>
I mean, it's not like HS-230 would condensate on the 300°C hot floor of the frier to get destroyed
<DocScrutinizer05>
it's just the vapor that gets into contact with the hot surface, and that's probably not that much substance
<DocScrutinizer05>
I even wonder if the decomposition products (HF etc) will recombine as soon as they cool down sufficiently
<DocScrutinizer05>
maybe not, since it's basically a polymer aiui
<whitequark>
DocScrutinizer05: (build modified deep friers) something I'd be pretty interesting in :)
<whitequark>
(decomposition products) to my best knowledge, they immediately fly away and go on to destroy everything good in this world
<DocScrutinizer05>
whitequark: any suggestions for product spec welcome. Like "special lid with integrated cooler for condensing Galden vapor before it escapes the tub. Operates on water or a mixture of water and ice. Condensed Galden flows down to bottom of fryer tub from a special tap directing the liquid to the wall of the tub where it runs down without getting into contact with the PCB"
<DocScrutinizer05>
I think the floor (heater element) temperature sensor may autodetect when boiling temperature got reached (delta-temp/t) and the controller doesn't try to increase temperature above that point. Or, nore specifically: when controller notices floor temperature rising a maybe 3°C above that temperature plateau and the vapor level sensor doesn't detect vapor reaching the sensor and heating it up as expected, then the controller
<DocScrutinizer05>
thorows "GALDEN VOLUME TOO LOW!" error and shuts down
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<DocScrutinizer05>
when floor temperature reaches - say - 250°C without controller sensing any plateau: -> error: "GALDEN MISSING!"
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<whitequark>
DocScrutinizer05: I want to get my hands on the live process first
<whitequark>
idle speculation isn't really very productive if you aren't even familiar with the thing you're trying to make
<whitequark>
talking about condensing galden... I *suspect* this is not very important, due to low vapor pressure => meaning it stays near the liquid?
<whitequark>
also very high density of vapor as well
<whitequark>
you want to operate it in a way where galden vapor does not overflow the tub at all
<whitequark>
(heating element) I think you should just use a standard PID controller algorithm. I mean, why not?
<whitequark>
(detecting overtemp and telling user that there's no galden) yes, that's an excellent idea
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<DocScrutinizer05>
whitequark: when you purr a litre of Galden into the fryer and then cook it at 2kW, it inevitably will escape the fryer sooner rather than later
<whitequark>
I wonder the exact degree of that
<whitequark>
hence see above, want to get my hands on the process. Fortunately how much galden has escaped is very easy to measure.
<DocScrutinizer05>
you can simulate with water
<DocScrutinizer05>
eventually the pipe on nozzle of your kettle will start to whistle
<DocScrutinizer05>
sure, that's not the supposed operation mode of a Galden VPS equipment
<DocScrutinizer05>
so consider it the outer safety containment and cooling of a nuclear reactor. Usually not active but for sure not useless
<DocScrutinizer05>
It just came to mind while pondering another type of cooling: some pipes with water cooling at the bottom of tub, to shut down the process in an instant when you start the water flow through the tubs
<whitequark>
DocScrutinizer05: sounds like overkill
<whitequark>
thought about galden escaping: think of the diagrams provided by VPS vendors
<DocScrutinizer05>
probably, particularly since you usually want slow gradients, not steep ones
<whitequark>
in the working area there is significant temperature gradient, with most of space above PCB being lower than Tb
<whitequark>
it really has no other way to escape than over the edges of the pot, and edges are cold => it condenses and flows down
<DocScrutinizer05>
I meant gradients over time, not over dimension axis
<DocScrutinizer05>
aka profile
<whitequark>
nono, I'm talking about escaping now. not the water cooling thing (later about that)
<whitequark>
so I think it would be sufficient to monitor temperature of the bottom of the pot (aka working area) *and* of the top of the pot (aka condensation area)
<DocScrutinizer05>
yes, exactly
<whitequark>
if bottom is too cold? not yet ready. too hot? alert, no galden. top is too hot? shut the thing down
<whitequark>
it really would be much better than fiddling with ice and so
<whitequark>
that'd really be a nuisance
<DocScrutinizer05>
but in case that control runs away, your pot will "overcook"
<whitequark>
thermofuse?
<whitequark>
like in my laminator.
<whitequark>
or better: control *and* thermofuse set 5°C higher
<whitequark>
maybe 10°C
<DocScrutinizer05>
nonono, you can't do that since you may ise different Galden
<whitequark>
ah, true.
<whitequark>
duplicate control circuits?
<DocScrutinizer05>
you could place a hard fuse at maybe 150°C at very top of pot
<whitequark>
possibly 2 circuits with 2 thermocouples for each
<DocScrutinizer05>
but it's already too late when that one engages
<whitequark>
well, you definitely need a fuse at 280°C at bottom
<DocScrutinizer05>
sure
<whitequark>
(hottest galden is ht-270)
<DocScrutinizer05>
I said 260
<DocScrutinizer05>
mhm
<whitequark>
though ht is heat transfer, ls is vps
<DocScrutinizer05>
I'm reluctant to go beyonf 260, since with titan around it already decomposes at that temperature
<whitequark>
also PCBs delaminate above 260 in mere minutes
<whitequark>
I've investigated that just today
<DocScrutinizer05>
hehe
<whitequark>
unless you have really high-quality specialized FR4 you have 1-2 minutes before delamination
<whitequark>
no, not experimentally ;)
<whitequark>
found some papers
<whitequark>
I was searching for a suitable activation agent for copper plating
<DocScrutinizer05>
aaah
<whitequark>
and most organic salts of copper decompose at least at 260, and that's lower bound
<whitequark>
so it's pretty sad on that front
<whitequark>
I'll still order oxalate, acetylacetonate, formate and citrate to test whether they're suitable
<whitequark>
but they are likely not
<DocScrutinizer05>
so it all fails with unavailability of that hypophosphoric acid?
<whitequark>
apparently hypophosphites are the ultimate sweet spot for copper plating
<whitequark>
it's hard to find anything even nearly as good
<whitequark>
whoever put that on DEA Schedule I, fuck you
<DocScrutinizer05>
:nod:
<whitequark>
a guy on RU forums did some experiments
<whitequark>
apparently: acetate has too high temp, turns into carbon
<whitequark>
about 250-300°C decomposition, also emits vinegar vapors (not good)
<whitequark>
oxalate: insoluble in water but readily forms suspensions. decomposition is above 350-400°C
<whitequark>
likely 500°C
<DocScrutinizer05>
eew
<whitequark>
exactly
<DocScrutinizer05>
there's probably a reason why this got patented
<whitequark>
so I'm still going to order that. I know a good inorganic chemist, maybe he'll help me to find something workable
<whitequark>
a catalyst sounds about right for this case
<whitequark>
I'm sure there must be *some* research
<whitequark>
(patented) patented was not just hypophosphite method itself but a variation of it
<whitequark>
namely he oversaturated the solution with calcium hypophosphite so that there's always a maximal amount of hypophosphite anions in the solution
<whitequark>
this gives far superior plating quality
<whitequark>
like, before this modification it didn't pass GOST standard check
<whitequark>
and I can frankly tell that USSR-era GOST standards on PCBs is not the strictest in the world
<DocScrutinizer05>
aaah
<DocScrutinizer05>
never heard of GOST
<whitequark>
really? there's a GOST crypto algorithm in openssl even
<DocScrutinizer05>
anyway, to ideas came to mind, dunno how much of a value in any of them: a) use some other metal, you don't need copper as conductive basis for any galvanic copper plating to a PCB, any conductive very thing coating might do.
<whitequark>
right
<whitequark>
but, several papers I've read mention that copper salts decompose at a *lower* temperature than other metal salts
<whitequark>
rather significantly so
<whitequark>
(and the mechanism is not currently fully known :)
<whitequark>
there's a well-known another process, it uses PdCl2
<whitequark>
that costs about as much as you may imagine
<DocScrutinizer05>
b) use some kind of "glue" coating that evaporates or decomposes, and dunk all that into an emulsion of nanocopper in water or whatever liquid. should make particles stick to PCB, later you evaporate the glue and particles stay
<whitequark>
hm.
<DocScrutinizer05>
3rd of my 2 ideas: use other forms of energy than mere slow heating to 242.42°C. Like flashlight, laser, microwave, hot air flush at 3000°C, etc
<DocScrutinizer05>
UV light
<DocScrutinizer05>
dunno, there are more than just one way to skin the cat
<whitequark>
haha, I love this proverb
<DocScrutinizer05>
think of good ole photography: silver iodine?
<whitequark>
hmmm
<whitequark>
that may actually be a good idea
<DocScrutinizer05>
silvernitrate?
<DocScrutinizer05>
how did they build mirrors in the old days?
<whitequark>
I think silver nitrate is actually one of possible replacements in pdcl2 in that process I've read about
<whitequark>
-Palladium chloride (can be successfully replaced by platinum chloride or, in extreme cases, silver nitrate)
<whitequark>
>in extreme cases
<whitequark>
here "extreme" means "extreme poverty" I guess
<whitequark>
(it's not what it said initially :D)
<DocScrutinizer05>
hehe
<DocScrutinizer05>
platinium chloride, wtf?
<whitequark>
no idea why is it needed
<whitequark>
catalyst?
<DocScrutinizer05>
I can't spot why it's *needed* to apply solution to holes with a syringe
<whitequark>
well, I have one guess
<DocScrutinizer05>
seems it just felt natural to the original author
<whitequark>
what would you use instead of syringe?
<DocScrutinizer05>
anyway, sounds like a job for your CNC solderpaste spreader extension
<whitequark>
oh, that... hm. that's an option
<DocScrutinizer05>
err, I would try to dunk the PCB into a bath of the solution, maybe move it vigorously to make solution enter all holes
<whitequark>
yes, exactly
<whitequark>
now think, you have 1-2ml of your precious metal salt in a syringe
<whitequark>
now you need a *bath* of that
<whitequark>
sounds a bit expensive doesn't it?
<DocScrutinizer05>
maybe the stuff is just too expensive to prepare and use large amounts of solution to allow that process?
<whitequark>
exactly
<DocScrutinizer05>
;-D ^^^
<DocScrutinizer05>
you might be able to come up with drastically improved variations, regarding amount of solution needed
<whitequark>
hmmm
<DocScrutinizer05>
think of a bag with 5ml of solution and the PCB, sealed without air inside, then place that to vacuum
<whitequark>
I suspect the Pd is not catalyst though
<whitequark>
but is the actual thing which is deposited initially
<whitequark>
ooh look
<whitequark>
DocScrutinizer05: another one of your guesses was right
<whitequark>
"Excimer lamp-induced decomposition of platinum acetylacetonate films for electroless copper plating"
<whitequark>
>Photo-induced decomposition of platinum acetylacetonate films using an excimer VUV source of 172 nm radiation is reported. VUV irradiation of a substrate coated with platinum acetylacetonate film results in the formation of platinum, which acts as an activator for copper plating by means of a subsequent electroless bath process.
<whitequark>
not suggesting to use that though, 172nm UV is highly carcinogenic and causes cataracts
<DocScrutinizer05>
yeah, hard UV is a tad nasty to deal with, but not unfeasible
<whitequark>
true words of the guy who suggested "exploding wire method" ;D
<DocScrutinizer05>
dunno if 172nm already gets into the range that really becomes impossible to handle since plain air and other gasses absorb it
<whitequark>
DocScrutinizer05: a quick search reveals that gasses don't absorb UV at that freq, rather water vapor does
<whitequark>
and no, seems still within usable range
<whitequark>
~1-2 orders of magnitude worse than visible spectrum
<whitequark>
though no, don't take my word for it. needs further investigation
<DocScrutinizer05>
chip waver exposure by hard UV is done in vacuum, but I guess that's another class of UV
<whitequark>
well... no, I was wrong
<whitequark>
UVC (100-200nm) is blocked by O2
<whitequark>
so that needs vacuum even
<DocScrutinizer05>
eventually they had to switch from lenses made of bizarre expensive material to concave mirrors since the lens material wasn't able to cope with the UV wavelength
<whitequark>
plus what exactly will you make UVC with? arc lamp?
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<DocScrutinizer05>
yeah, light sources for hard UV are another problem
<DocScrutinizer05>
so that clearly classifies as "not feasible on a DIY level"
<whitequark>
definitely
<DocScrutinizer05>
they use similarly biszarre light sources in chip manuf
<whitequark>
>Masks themselves (due to the nature of x-rays) are made up of light, thermally stable, extremely flat, “optically transparent” low-atomic-weight materials, such as beryllium (which is absolutely the best, but costs like the GDP of Argentina)
<whitequark>
GDP of Argentina hahaha
<DocScrutinizer05>
sure, it takes a while from emerging new technology to industrial level mass usage
<whitequark>
anyway beryllium masks are evil apart from being expensive
<whitequark>
Be is really toxic
<DocScrutinizer05>
check "UV lithography"
<whitequark>
So, elements such as platinum, gold (nice 'cuz they don't oxidize, lousy 'cuz they're as soft as butter), or tungsten, or especially uranium (which has its own problems with oxidation) are the masking 'stuff'.
<whitequark>
uranium!!
<DocScrutinizer05>
the predecessor of x-ray lithography
<whitequark>
now I knew depleted uranium can be used highly successfully if you need a really heavy brick
<whitequark>
but don't they have to keep work area *really* clear of any radiation? and while depleted U is not very radioactive it will still crap all over occasionally
<DocScrutinizer05>
x-ray lithography is probably also out meanwhile (I don't follow closely anymore). Maybe now electron beam is the thing they use
<DocScrutinizer05>
all of that not really an alternative for anything PCB related
<whitequark>
right, electron beam
<whitequark>
definitely not for PCBs :)
<DocScrutinizer05>
just a funny read when you got the rant of "we want open source hw manufacturing, down to the roots of the creation chain" zealots in mind
<whitequark>
well that would certainly be nice
<whitequark>
but people tend to severely underestimate the real complexity and cost of all the tasks
<whitequark>
by 5-10 orders of magnitude, I think :D
<DocScrutinizer05>
yes, by a factor of 10^6 to 10^12
<DocScrutinizer05>
hah
<whitequark>
hehe
* whitequark
is watching live stream from UA
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<whitequark>
DocScrutinizer05: that guy from µC.net responded with a quote... 110 eur for 0.5L
<whitequark>
I say this is a really good price
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<DocScrutinizer05>
yes, definitely
<whitequark>
so... will still phone a local distributor, but they likely don't want to work with me
<whitequark>
4/5 list MOQ=100kg
<whitequark>
what ever are you even going to do with 100kg of galden
<whitequark>
that's probably enough for a small country for a year
<DocScrutinizer05>
operate a *real* vapor phase?
<DocScrutinizer05>
sinze of two fridges, or 4
<DocScrutinizer05>
size*
<whitequark>
mm, perhaps
<whitequark>
anyway I'm going to sleep
<DocScrutinizer05>
o/
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<wpwrak>
AAH. finally a timer signal. what was missing is to un-suspend timers in debug mode. gnargh.
<DocScrutinizer51>
hah!
<DocScrutinizer51>
\o/ EDF deadline process scheduler in kernel 3.14
<pcercuei>
EDF?
<DocScrutinizer51>
earliest deadline first
<DocScrutinizer51>
real realtime
<DocScrutinizer51>
also: kGraft yay! finally ksplice for the masses
<pcercuei>
that's great
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<whitequark>
DocScrutinizer05: >"of course is it ok for me to ship to Moscow, why not?"
<whitequark>
I see he never actually tried it :D
<DocScrutinizer05>
LOL
<DocScrutinizer05>
him shipping is no trouble at all. You *receiving* it might well be though
<DocScrutinizer05>
customs might have a hard time verifying the content of this bottle is actually what's written on the outside, and not any listed substance
<whitequark>
ah
<whitequark>
well, the right thing to write in declaration is "solvent fluid", that is even technically true
<DocScrutinizer05>
non-toxic, non-corrosive
<DocScrutinizer05>
non-flamable
<whitequark>
right
<DocScrutinizer05>
note that this soup is also used for lubricant and for vacuum pumps
<DocScrutinizer05>
and even to drown mice and scare them to death err not ;-P
<DocScrutinizer05>
I need to start a test - see how long it takes til a drop of that stuff vanishes on glass, at room temperature
<whitequark>
drown mice, hmm
<whitequark>
(drop vanishes on glass) yep, an important test
<DocScrutinizer05>
are you thinking of shipping a drowned living mouse in the bottle? X-P
<DocScrutinizer05>
will shock the shit out of customs
<wpwrak>
afaik they don't survive the ordeal for very long
<DocScrutinizer05>
prolly not, they are dieing from dehydration I guess
* DocScrutinizer05
picks a straw and a drinking glass
<wpwrak>
it seems that they day a short while after you take them out of the liquid. not sure of what. maybe they simply succeed in convincing themselves that this experience can't have been survivable.
<DocScrutinizer05>
while mice actually can do this (die from shock), I suspect here the problem is lungs clogged with liquid, thus blocking gas flow to alvioles
<DocScrutinizer05>
basically a very severe lung emphysema
<DocScrutinizer05>
err, nope. dang, emphysema isn't the right term
<DocScrutinizer05>
almost but not really
<DocScrutinizer05>
lung oedema
<DocScrutinizer05>
to not suffer this, I'll stop smoking this cig before I proceed with the Galden
<DocScrutinizer05>
and I'll place the glass with the drop to evaporate outside
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<DocScrutinizer05>
test started
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<DocScrutinizer05>
and already failed. the drop isn't visible though still some liquid is there
<DocScrutinizer05>
I seen something moving when tilting the glass
<DocScrutinizer05>
though I already had to look *very* closely
<DocScrutinizer05>
seems optical density of galden is just too close to that of normal glass
<DocScrutinizer05>
when I could find a glass with roughened (etched) surface, I bet this would be easier to see
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<whitequark>
DocScrutinizer05: wait, you got yourself some galden?!
* whitequark
is envious
<DocScrutinizer05>
sure, since weeks, I mentioned it here
* DocScrutinizer05
just starts to wonder how much HF might be solved in Galden, to begin with
<DocScrutinizer05>
when I let's say drop a 5mm glowing hot steel ball into the bottle, will HF and other shit escape the bottle immediately or will it much rather solve in Galden?
<DocScrutinizer05>
how much of that effect might have happened in factory already, during production? How much due to aging, by cosmic particles or dunno what?
<whitequark>
DocScrutinizer05: (hot steel ball) I would fully expect it to escape immediately. you'd get hot HF vapours with very low density
<whitequark>
(during factory) I'd imagine they clean it carefully from HF, because HF is highly corrosive and you can't really sell your liquid as "chemically inert"
<DocScrutinizer05>
sure, but wouldn't they solve in the galden around them?
<whitequark>
HF is a gas
<DocScrutinizer05>
oxigen too
<DocScrutinizer05>
Galden is known to solve gasses very good
<whitequark>
well. solubility of gasses in liquids is an unsolved problem in general as I have already found out
<whitequark>
so without experiment it is really hard to say for sure
<DocScrutinizer05>
it seems even H2O is solving easily in Galden, so you might call it hygroscopic
<whitequark>
I would really think that at the decomposition temperature *and* low pressure HF would not be soluble well in galden
<whitequark>
but that's my idle speculation
<whitequark>
well
<whitequark>
let's find out?
<DocScrutinizer05>
o.O
<whitequark>
actually, no, shouldn't be needed
<whitequark>
such data should be contained in MSDS or related documents
<DocScrutinizer05>
I already heated a dropplet of that stuff on a spoon, with my lughter :-o
<whitequark>
lol
<DocScrutinizer05>
lighter even
<whitequark>
but how would you detect HF?
<whitequark>
also, that's a bit suicidal
<DocScrutinizer05>
exactly, that's why I won't repeat that
<whitequark>
I mean, if you were a bird, you'd drop dead already; birds are extremely sensitive to ppm concentrations of fluorocarbon decomposition products
<whitequark>
though after reading that I want to live in a forest or something :S
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<whitequark>
DocScrutinizer05: btw, what happened after heating it in a lighter?
<DocScrutinizer05>
it vanished
<whitequark>
so, likely just evaporated
<whitequark>
but whatever miniscule quantities went to the flame decomposed to that toxic shit
<DocScrutinizer05>
maybe 5% got decomposed by flame
<DocScrutinizer05>
initial qty esimated a 0.01g
<whitequark>
I wonder, if you heated it over a container, something like a frying pan
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<whitequark>
would it condensate back on it?
<whitequark>
suppose no side wind
<DocScrutinizer05>
I seen it partially condensing at spoon further away from flame
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<DocScrutinizer05>
it kinda creeps away from the flame
<DocScrutinizer05>
well, I guess for this experiment to get really dangerous the stuff had to be VX, not Galden
<DocScrutinizer05>
or tritium-water
<whitequark>
tritium-water isn't really dangerous as it does not bioaccumulate
<whitequark>
and β¯-decays
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<DocScrutinizer05>
well, the tritium light on my keyring is forbidden in Germany
<DocScrutinizer05>
despite the immesurable amount of tritium gas inside
<DocScrutinizer05>
it has a radiation above a certain Becquerel
<whitequark>
because people are stupidly paranoid about radiation
<DocScrutinizer05>
that doesn't even escape the glas tube
<DocScrutinizer05>
but it *could*
<DocScrutinizer05>
when you destroy it
<DocScrutinizer05>
and gamma radiators are really evil when ingested
<whitequark>
and the whole milligram of T2 will go to air and in about three seconds go below natural background levels
<whitequark>
it's not gamma
<whitequark>
it's β¯
<DocScrutinizer05>
err beta
<whitequark>
and in this case it's not evil, you know why? because nothing in your body uses or accumulates H2 from air
<DocScrutinizer05>
can't pass a sheet of paper, but can shoot your DNA from an angstrom distance
<whitequark>
it'll just dissipate
<DocScrutinizer05>
yeah, unless you burn it to water, that is
<whitequark>
when you sit on a granite pavement you subject yourself to a higher risk
<whitequark>
I don't think it's even possible to burn that amount of T2, simply because it *doesn't burn* at that concentration
<whitequark>
at all
<whitequark>
you have min and max amounts of H2 and O2 for reaction to proceed
<DocScrutinizer05>
3H2 is for sure not dangerous, 3H2O though...
<DocScrutinizer05>
and it inevitably would react with oxygen from air to form 3H2O in a flame of a lighter
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* whitequark
sighs
<DocScrutinizer05>
I still dunno if it would be more dangerous than widespread natural occurrence of Radon in cellars
<whitequark>
shall I take absurdly low yearly exposure limits and prove that even by current paranoid official standards it is not dangerous at all?
<whitequark>
it'll probably start to become bad if you burn a pallet of those things
<whitequark>
even so doubtful
<DocScrutinizer05>
the effect is very similar to that of polonium and plutonium aiui
<whitequark>
polonium decays as α too, though
<DocScrutinizer05>
and I still wonder if that glolite keyring thing does emit xray. The energy of beta is some 25keV iirc
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<DocScrutinizer05>
for sure less than any crt tube, particularly color
<whitequark>
>In the early twentieth century, radiographers would commonly calibrate their machines by irradiating their own hand and measuring the time to onset of erythema.
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<DocScrutinizer05>
LOL
<DocScrutinizer05>
I still seen and *used* the shoe checker xray box in shoe shops
<DocScrutinizer05>
my mother got panic
<DocScrutinizer05>
must've been 1964, 65
<whitequark>
shoe checker?
<DocScrutinizer05>
they should've been outloawed by then, but in some cheesy little province town they had one still
<whitequark>
> that it made it more fun for kids to go to the shoe store
<whitequark>
fun for the whole family indeed
<DocScrutinizer05>
yea, I was damn mesmerized by that thing
<whitequark>
wait, how old are you exactly?
<whitequark>
1964?!
<DocScrutinizer05>
when my mother didn't watch for a minute, I managed to sneek to it and start it
<DocScrutinizer05>
shhhh!
<whitequark>
I see there's something time doesn't change :D
<DocScrutinizer05>
3 years later I wouln't have approached that thing, by no means. But in that age my education wasn't sufficient, regarding stuff like xray. Only sufficient to design an electromotor without ever having seen one from inside
<DocScrutinizer05>
and I don't even know what's been written on the sign they placed on that pedoskop - prolly "Achtung! Roentgenstrahlung! Gefahr!". I didn't know to read by then
<DocScrutinizer05>
except digits and "LOTTO" ;-P
<whitequark>
so you designed your first electric motor before even learning to read? :D
<DocScrutinizer05>
yep
<DocScrutinizer05>
age of 4
<DocScrutinizer05>
or 5
<DocScrutinizer05>
it worked with only one statically mounted electromagnet and a rotor with three steel poles
<DocScrutinizer05>
and for sure you had to give it a kick to make it start spinning, but it would have worked
<DocScrutinizer05>
I drawn it to a sheet of paper and shown it to my dad. Damn been I proud when he said "yes, that's basically how motors work"
<whitequark>
nice
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<DocScrutinizer05>
that's why I still remember it, I guess
<DocScrutinizer05>
while other experiments like building a Marconi-alike "transmitter" from a buzzer and 2 m of antenna wire are more or less forgotten
<DocScrutinizer05>
and better stay forgotten, I guess I annoyed roundabout 100 neighbours with that jammer
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<DocScrutinizer51>
wpwrak: hey, I just compared your food to new zealand ox. Not bad either!
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