The Official Funny Stuff Thread™
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As an occasional amateur guitar amp tech, I usually discharge capacitors with a large value resistor, something like 100k ohms. The main filter capacitors in a typical guitar amp will be charged up to 350 - 550 volts depending on model. I know some people just touch the terminals with a screwdriver and let it arc but that doesn't seem too safe to me. Better to slowly discharge over several minutes.
Once it's discharged I use a small alligator clip lead to leave the capacitors shorted out, sort of like a lockout-tagout thing. I can tell at a glance they've been discharged already and there's no way they'll kill me.
I don't know what the capacitance value is, but these things are usually huge.
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I know some people just touch the terminals with a screwdriver and let it arc but that doesn't seem too safe to me.
in that situation it's not that dangerous to you. but if things are a bit cramped that arc could cause some of the magic blue smoke to escape. ;-)
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most caps you'll run into can't store enough charge to do more than give you a rather nasty shock, but that doesn't mean you should be cavalier with them.
Well, we're talking about supercaps here. I forgot how to calculate the peak current on that, but I assume it can be quite high.
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supercaps
those.
yeah you want to be careful around those. those can kill you if you FSCK it up.
of course if you're taking the usual electric precautions they're not that bad. kist treat them with the same care you treat power mains and you'll be fine.
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IANAEE, though...
IAAEE, and I agree with subsequent comments, but
IC designers routinely deal with capacitances down in the fF (femtofarad) range
so I don't deal with those kinds of capacitors professionally. However, I first started learning about electronics from my dad back when vacuum tube TVs were the norm1, and I'm also a Ham Radio operator2, and pretty much anything with vacuum tubes3 has capacitors that will knock you on your ass if you touch them when they are charged (and they can stay charged when the device is turned off, and even unplugged).As an occasional amateur guitar amp tech, I usually discharge capacitors with a large value resistor, something like 100k ohms. The main filter capacitors in a typical guitar amp will be charged up to 350 - 550 volts depending on model. I know some people just touch the terminals with a screwdriver and let it arc but that doesn't seem too safe to me. Better to slowly discharge over several minutes.
It might, conceivably, damage the capacitor to discharge it too quickly, but other than that, not really dangerous (unless you're generating that spark in your garage full of gasoline vapor, or something like that). Here, just for the heck of it, is a graph of how long it will take for your capacitor to be safe to handle by discharging it through various values of resistor, given C = 1000µF and V0 = 500V, where I'm arbitrarily setting the "safe" threshold at 5V:
Not plotted here is the power dissipated by the resistor while it's discharging the cap. The 100kΩ resistor is going to get a bit warm. The 10kΩ is probably going to smell really bad. The 1kΩ resistor would do a fair impersonation of an incandescent light bulb for a few tenths of a second, if it lasts that long.1Even later "solid state" TVs had dangerous voltages for the CRT and related circuitry.
2Although I haven't done anything with it for about 20 years.
3High-power <abbr title=Radio Frequency">RF amplifiers, as well as snobbish audio equipment, may still use them. Microwave ovens definitely do.
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Isn't it quite dangerous to short out a cap like that? If it's charged, it would discharge rapidly, I think. IANAEE, though...
The reason the piece of wire is there is to keep the cap shorted; the shorting bar/jumper is put in right after the cap is discharged to keep certain physical phenomena within the capacitor from basically causing some of the charge to return. (Look up "dielectric absorption" and "soakage" if you want to know more about this.)
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Isn't it quite dangerous to short out a cap like that? If it's charged, it would discharge rapidly
Caps are stored in a shorted state so that they do not pick up a charge from electrostatic charge and etc. If you leave a capacitor in an un-shorted state for long enough, they will pick up a charge on their own. So the best way to store them is shorted, to keep you from having a nasty surprise when you run across them years later...
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Well this is confusing. I had assumed @Polygeekery was @HardwareGeek under a new username but that doesn't seem to be the case.
The 100kΩ resistor is going to get a bit warm.
On my guitar amp I've never actually seen more than 30 - 40 volts on the capacitors when the amp is unplugged and turned off, and normally it's in the 10 - 15 V range. (I think it's around 400V if plugged in and turned on.) I always check with a meter before touching anything, it seems mine leak a bit of charge so a 100k resistor works fine for discharging that last bit.
Yes it's a tube amp in case anyone is wondering.
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Well this is confusing. I had assumed @Polygeekery was @HardwareGeek under a new username but that doesn't seem to be the case.
It's somebody under a new name, but not me. I even recognize specific posts in his history, but I can't quite remember who he used to be.
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It's somebody under a new name, but not me. I even recognize specific posts in his history
From the mannerisms, I buttumed it was Intercourse. From this page http://what.thedailywtf.com/users/Intercourse/activity and the fact that "@int" doesn't autocomplete any suggestions, I feel pretty sure it is.
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Now that you mention it, I do seem to recall him asking for a name change. I remembered someone did; now I remember who and why. I think you're right.
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From the mannerisms, I buttumed it was Intercourse.
Yes, that's definitely who it is. I didn't change his name, but was surprised earlier to see a name I didn't recognize, and he was a TL3! I looked at his post history, and sure enough, that was @Intercourse.
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Now that you mention it, I do seem to recall him asking for a name change.
Yeah, he had second thoughts about the maturity of the name, IIRC.
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Yeah, he had second thoughts about the maturity of the name, IIRC.
I think the joke made more sense in early days.
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Discourse still manages to intercourse-up pretty often.
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From the mannerisms, I buttumed it was Intercourse
and i helped him pick the name!
and by helped i mean i suggested at least a dozen names and he rejected them all and eventually came up with his own.
and i helped!
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I think the joke made more sense in early days.
We have a winner!
I honestly had no intentions of sticking around this long, but you bastards grew on me.
Thanks to @accalia for helping pick a new name. She was wrong though. Not a single polygamy joke yet...
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I didn't change his name
@PJH did. Thanks again, much appreciated. So far, the change has been uncharacteristically smooth. I was online, he changed it, a hard refresh and all done.
Tomorrow all my badges will be gone and I will be TL0, but for now something appears to have worked fine...
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From the mannerisms, I buttumed it was Intercourse.
What mannerisms? The constant cursing? The ego? The arrogance? The disdain for blakeyrat?
Asking for a friend...
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Not a single polygamy joke yet...
i was going to give them more than about 8 hours to come up with that one....
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nope, couldn't keep a straight face!
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No polygamy for me. I prefer to disappoint one woman at a time...
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What mannerisms?
Just the way you speak. The way some people speak has somewhat of a fingerprint. If @accalia changed her name, we'd still know who it was by all the fox references and bad spelling.
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No polygamy for me. I prefer to disappoint one woman at a time...
Polyamory includes polyandry.
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Just the way you speak.
So what you're saying is...if a person wanted to be a convincing blakeyrat, all they need do is call everyone an idiot and talk about Mac Classic?
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If @accalia changed her name, we'd still know who it was by all the fox references and bad spelling.
more the spelling thant hte fox references. i'd likely drop the foxes if i went incognito.
maybe i'd switch to koalas.
INB4: yes i left thos speeling errrors in pn porpoise. these ones two. the gramming is due to the three shots of fermeented potato water...... vodka! that i've had in the past hour.
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So what you're saying is...if a person wanted to be a convincing blakeyrat, all they need do is call everyone an idiot and talk about Mac Classic?
That would be necessary but it might not be sufficient. I mean, _I could do that, but people would probably still be able to tell the difference.
Except I wouldn't talk up Mac Classics.
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If @accalia changed her name, we'd still know who it was by just the bad spelling.
FTFY
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due to the three shots of fermeented potato water.
You damned drunk. I knew I liked you for a reason...
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You damned drunk. I knew I liked you for a reason...
not durnk! just..... happily relaxed!
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The way some people speak has somewhat of a fingerprint.
Yes, I rather doubt that I could go incognito successfully. I'm afraid the tendency toward rather formal writing and rampant pedantry would leak through, even if I were consciously trying to change my style.
Edit: And overuse of the word "rather."
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I'm afraid the tendency toward rather formal writing
Must be why we were sort of mistaken for each other...
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Yes, I rather doubt that I could go incognito successfully. I'm afraid the tendency toward rather formal writing and rampant pedantry would leak through, even if I were consciously trying to change my style.
You can somewhat do it--on the web, that is--if you are willing to spend time editing your posts afterwards to get rid of mannerisms. Like anything else, it takes practice.
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You can somewhat do it--on the web, that is--if you are willing to spend time editing your posts afterwards to get rid of mannerisms.
You'd probably be better off going to a completely unrelated forum, and developing your alter persona over there, if you wanted to have it present as distinct from your original online self.
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Not a single polygamy
I've laughed at all of them in my mind ... you should have been there ... it was hilarious
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I've laughed at all of them in my mind ... you should have been there ... it was hilarious
shudder The mere thought of peering in to your Belgium-ing mind, scares me. <Just playing with the filter>
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You'd probably be better off going to a completely unrelated forum, and developing your alter persona over there, if you wanted to have it present as distinct from your original online self
No doubt
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if they navigate to that page successfully the first time, and every time give them a flapping medal! (and a job)
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Looking at that query string, I'm guessing that "action=viewJob&jobID=601448" (and maybe "transfer=0") is probably good enough to get you where you need to go, and the rest is just fluff for their internal tracking, or whatever. I'm not sure I want to go to a job website from my work computer to test my theory, though.
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Old story, but pretty WTF-y nonetheless.
I wonder if it was purple?
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Seriously, what else could you say to that reply? I would be legitimately speechless if someone had sent that reply to me...
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I wonder if it was purple?
Police still aren't sure why Creighton chose to use a device that mimics the male sex organ to pass her drug test.
This really got stranger after every line I read.
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Seriously, what else could you say to that reply? I would be legitimately speechless if someone had sent that reply to me...
I agree, the guy clearly has no idea what an apostrophe even is, let alone how to use one.
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Yes, DDG, that's exactly what I wanted.
SomeMost of the other results are just as good:
If anyone cares, two out of the first seven results were actually somewhat relevant.