1590: "The Source"

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Re: 1590: "The Source"

Postby yyy » Thu Oct 15, 2015 6:25 am UTC

The generator is activated by reading randomly named scrolls.

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Re: 1590: "The Source"

Postby Coyne » Thu Oct 15, 2015 6:43 am UTC

I suspect this comic actually is a broader commentary on the things humans make. Consider atomic bombs, pet rocks, 90% of weight loss plans: Why did we ever have those, anyway?
In all fairness...

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Re: 1590: "The Source"

Postby ijuin » Thu Oct 15, 2015 7:01 am UTC

Usually when I hear a high pitched whine I assume that I am having another tinnitus attack.

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Re: 1590: "The Source"

Postby xtifr » Thu Oct 15, 2015 7:22 am UTC

orthogon wrote:"High-pitched hum" is an oxymoron. A hum is specifically a low-pitched continuous sound. What you have, if it's high-pitched and continuous, is a whistle.

No, high-pitched hum is not an oxymoron. Believe it or not, there is a range of frequencies that can be described as a hum. And what, exactly, would you call hums that occur at the higher end of that frequency range? (I'm trying very hard not to say "duh" here.)

Now I agree that not all electronic background noises are reasonably described as hums. I just went out in the laundry room, and noticed that one of the florescent tubes we have there was making a sound that would more accurately be described as a grind or whine. Too high-pitched to be a hum. Nevertheless, sitting right here at my computer, I can hear a couple of high-pitched hum generators running. I can easily hum at much lower frequencies. Much, much lower.
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Re: 1590: "The Source"

Postby Wee Red Bird » Thu Oct 15, 2015 7:37 am UTC

xtifr wrote:Now I agree that not all electronic background noises are reasonably described as hums. I just went out in the laundry room, and noticed that one of the florescent tubes we have there was making a sound that would more accurately be described as a grind or whine. Too high-pitched to be a hum. Nevertheless, sitting right here at my computer, I can hear a couple of high-pitched hum generators running. I can easily hum at much lower frequencies. Much, much lower.


Arrrgh, its early in the morning, still a little dark outside, and a florescent tube above my desk is doing that 'plink plink' noise with a bit of humming in between. Throw in the disco strobe effect and I'm about to crack. Aaarrrrggghhhhh. If it wasn't behind a plastic sheet I'd take the bloody thing out with my mug.

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Re: 1590: "The Source"

Postby jonhaug » Thu Oct 15, 2015 8:45 am UTC

cellocgw wrote:A cup of sugar, added covertly to his fuel tank, will solve that problem.

So anyway, all we have to do is convert from 50/60 Hz mains to 30kHz AC, and we won't be able to hear any humming :mrgreen:


A well known myth. Have you ever tried this? (Reference to snopes dot com deleted as xkcd flagged it as spam. :-()

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Re: 1590: "The Source"

Postby Sandor » Thu Oct 15, 2015 10:48 am UTC

airdrik wrote:I envy those who can't hear these very high pitch noises (such as my wife who e.g. can't hear the hum of our CRT TV when it is on) as these noises are all very annoying.

In the UK, you sometimes get shopkeepers using The Mosquito, a device that generates a 17.4 kHz whine to try and deter teenagers from hanging around, without affecting older folk. They're somewhat controversial.

airdrik also wrote:I'm surprised it only took him 5 panels to find the source as it is often very hard to tell which direction such high pitched hums come from, especially when you turn your head and at various angles/positions the sound might cancel itself out, so all you really get is a game of hot/cold where you can't always tell if you are getting any warmer.

I sometimes work in a computer room, and trying to track down a beeping computer (presumably because of a hardware failure) in a room with 1000's of them can get very frustrating.

Crissa wrote:Yesterday, PG&E was re-stringing the high-voltage lines in our neighborhood, so the power was out. Nothing like the power going out to remind you of all the tiny hums and whines of various devices.

And it's eerie how quite a computer room is when the power goes off. Those places are normally loud, but you get used to it after a short while. A powered-off computer room is somehow very spooky.

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Re: 1590: "The Source"

Postby cellocgw » Thu Oct 15, 2015 11:31 am UTC

jonhaug wrote:
cellocgw wrote:A cup of sugar, added covertly to his fuel tank, will solve that problem.

So anyway, all we have to do is convert from 50/60 Hz mains to 30kHz AC, and we won't be able to hear any humming :mrgreen:


A well known myth. Have you ever tried this? (Reference to snopes dot com deleted as xkcd flagged it as spam. :-()


No, I'm not quoting an urban legend: I'm quoting some BS I made up on the spot. All the same, if everything in your house ran at 30kHz (including your refrigerator, furnace pump/blower, ...) and there were no subharmonics, ... win!
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Re: 1590: "The Source"

Postby mathmannix » Thu Oct 15, 2015 12:38 pm UTC

cellocgw wrote:
jonhaug wrote:
cellocgw wrote:A cup of sugar, added covertly to his fuel tank, will solve that problem.

A well known myth. Have you ever tried this? (Reference to snopes dot com deleted as xkcd flagged it as spam. :-()

No, I'm not quoting an urban legend: I'm quoting some BS I made up on the spot.

You just happened to make up the BS idea of stalling a car by putting sugar in the gas tank, which is already a widely-known urban legend?
Here is the snopes article for reference:
http://www.snopes.com/autos/grace/sugar.asp
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Re: 1590: "The Source"

Postby Neil_Boekend » Thu Oct 15, 2015 12:46 pm UTC

cellocgw wrote:All the same, if everything in your house ran at 30kHz (including your refrigerator, furnace pump/blower, ...) and there were no subharmonics, ... win!
The amount of power used by a normal house running at 30 KHz? It would have certain advantages: No batteries in the remote anymore, since the power requirements for a remote can easily be picked up out of the air. Same with the smoke alarms and many other battery operated devices. They could just have a coil and a capacitor, tuned to 30 kHz.
It would bug the hell out of the "Electromagnetic radiation is bad" crowd though. And many metal objects would get hot, especially with a length of 5 meters (1/2 λ). Such as steel structural elements of your building. All that heat would be loss (doubly so in the summer with the airco on.).
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flicky1991 wrote:I'm being quoted too much!

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Re: 1590: "The Source"

Postby Keyman » Thu Oct 15, 2015 1:19 pm UTC

mathmannix wrote:
cellocgw wrote:
jonhaug wrote:
cellocgw wrote:A cup of sugar, added covertly to his fuel tank, will solve that problem.

A well known myth. Have you ever tried this? (Reference to snopes dot com deleted as xkcd flagged it as spam. :-()

No, I'm not quoting an urban legend: I'm quoting some BS I made up on the spot.

You just happened to make up the BS idea of stalling a car by putting sugar in the gas tank, which is already a widely-known urban legend?
Here is the snopes article for reference:
http://www.snopes.com/autos/grace/sugar.asp

I know it's a terrible thing, and of course I've never done it, and never would, but to find out it was pretty much useless was...somehow disappointing.
I did like their last point though:
Accordingly, the best way to gain revenge on someone through the "sugar in the gas tank" prank might be to simply play on the belief rather than the reality — just sprinkle a fair amount of sugar on the ground beneath the opening to the fuel tank of your victim's car and leave an empty sugar sack in a conspicuous spot near the vehicle. Then sit back and watch your victim go wild trying to figure out how to deal with all that sugar he assumes is now in his gas tank.
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Re: 1590: "The Source"

Postby speising » Thu Oct 15, 2015 3:02 pm UTC

Nowadays, the first thing they would do is probably to google "sugar gas tank" and find the snopes page.

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Re: 1590: "The Source"

Postby Neil_Boekend » Thu Oct 15, 2015 3:11 pm UTC

Or maybe they have seen Mythbusters season 2 episode 7.
Mikeski wrote:A "What If" update is never late. Nor is it early. It is posted precisely when it should be.

patzer's signature wrote:
flicky1991 wrote:I'm being quoted too much!

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Re: 1590: "The Source"

Postby deskjethp » Thu Oct 15, 2015 3:13 pm UTC

Znirk wrote:My office has an HPHG, but it's labeled as an HP Laserjet M551.


Typical HP printers. They aren't to be trusted.
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Re: 1590: "The Source"

Postby Zylon » Thu Oct 15, 2015 3:45 pm UTC

orthogon wrote:"High-pitched hum" is an oxymoron. A hum is specifically a low-pitched continuous sound. What you have, if it's high-pitched and continuous, is a whistle.

That's even dumber than calling it a hum. Power supplies do not whistle, they whine. Tea kettles whistle.

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Re: 1590: "The Source"

Postby orthogon » Thu Oct 15, 2015 4:00 pm UTC

HES wrote:
orthogon wrote:That just isn't one of the meanings that the noun has.

Except for the part where we're all using it that way.


The specific meaning I was talking about was "the sound of somebody humming", which is not the way most of y'all are using it; only mathmannix and xtifr have used it that way as far as I can tell.

xtifr wrote:No, high-pitched hum is not an oxymoron. Believe it or not, there is a range of frequencies that can be described as a hum. And what, exactly, would you call hums that occur at the higher end of that frequency range? (I'm trying very hard not to say "duh" here.)


Well, ok, you can have a high-pitched hum in the same way that Hiroshima was hit by a small atom bomb, which is to say relatively speaking.

Zylon wrote:
orthogon wrote:"High-pitched hum" is an oxymoron. A hum is specifically a low-pitched continuous sound. What you have, if it's high-pitched and continuous, is a whistle.

That's even dumber than calling it a hum. Power supplies do not whistle, they whine. Tea kettles whistle.

A whine is kind of midrange. If I had to put figures on it, I'd say hum: <1kHz, whine 500Hz-4kHz, whistle >2kHz; in the overlap ranges the distinction depends on the harmonic content and stability. A whine is likely to vary in pitch over time.
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1590: "The Source"

Postby hamjudo » Thu Oct 15, 2015 4:39 pm UTC

Neil_Boekend wrote:The amount of power used by a normal house running at 30 KHz? It would have certain advantages: No batteries in the remote anymore, since the power requirements for a remote can easily be picked up out of the air. Same with the smoke alarms and many other battery operated devices. They could just have a coil and a capacitor, tuned to 30 kHz.
It would bug the hell out of the "Electromagnetic radiation is bad" crowd though. And many metal objects would get hot, especially with a length of 5 meters (1/2 λ). Such as steel structural elements of your building. All that heat would be loss (doubly so in the summer with the airco on.).


You're not taking this thought experiment seriously. You got the implied part about replacing all of the motors, transformers, circuit breakers, and power supplies, but missed the implied part about replacing all of the wiring.

Back in 1981 or 82, I took a physics course which covered the theory of this stuff in extreme detail. Alas, I did not retain it. Thus forcing me to ask a question where I should know the answer, but I don't. Would twisted pair wiring be sufficient with 30Khz power, or would we need to use coaxial cable?

I've got a copy of the National Electrical Code Handbook, from 1993. It is a thick book (about 6 cm). Most of the rules in the handbook were created after multiple fires, injuries, and/or deaths. I'm sure the current version is even thicker, given that there have been a couple more decades of fires, injuries, and deaths since that book was written. Adding rules for 30Khz wiring would probably make it a 10 cm book, plus require a whole bunch of fires, injuries, and deaths.

Obviously, the right thing to do, is to skip high frequency AC power, and get prepared for high voltage DC power. High voltage DC power transmission lines are already cost effective in a few situations. If the power line is superconducting, DC is the only way to go. Superconducting lines are much smaller per megawatt, than equivalent AC power lines (even with the added space for the cryogenics). So it is often cheaper to go superconducting, than to make a tunnel bigger.

DC power lines are smaller if made out of plain old aluminum or copper, but they still require a lot of space and money for the equipment to convert from AC to DC and vice versa. It makes sense for very long terrestrial power lines, and for comparatively shorter lines that need to be buried beneath a body of water. It is an absolute requirement for power lines that connect grids that aren't synchronized.

The conversion equipment is getting cheaper, smaller, and more reliable over time. So high voltage DC transmission will eventually become cost effective for the power lines that connect substations. After conversion equipment becomes cheaper than transformers for individual houses, we will see DC power to the meter. Then, running DC power within houses will start to make sense.

I expect the walls of my grandchildren's houses will have DC outlets. At that point DC to legacy AC adapters should be very efficient, small, and inexpensive.

Also, the National Electrical Code already has safety rules for DC, so we won't need a new set of fires, injuries, and deaths. Although, I'm sure there will be quite a few as high voltage DC use scales up. Hopefully, there will be less than if we stayed on AC.

Now is the time to lobby standards bodies, and legislatures for acoustic limits for power conversion equipment. Many current DC-DC converters emit high pitched whines. That should not be allowed. We will have the technology.

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Re: 1590: "The Source"

Postby Shamino » Thu Oct 15, 2015 5:33 pm UTC

Wee Red Bird wrote:Arrrgh, its early in the morning, still a little dark outside, and a florescent tube above my desk is doing that 'plink plink' noise with a bit of humming in between. Throw in the disco strobe effect and I'm about to crack. Aaarrrrggghhhhh. If it wasn't behind a plastic sheet I'd take the bloody thing out with my mug.
Something in the fixture is worn out and needs to be replaced.

The plink-hum is the starter repeatedly trying and failing to strike an arc that will create the plasma needed to light the bulb. If you can see the starter itself, you will probably see a light glowing from inside it. Once the arc is struck and the bulb remains lit, the starter will stop trying to light the bulb and the noise will stop.

To fix the problem, start with the easiest solution - replace the bulb. If that doesn't work, replace the starter (assuming your fixture is an old enough design such that it has a replaceable starter.) If that doesn't work, you'll probably have to replace the ballast. Replacing a ballast can be a pain in the neck - it's often cheaper and easier to just replace the fixture instead.

See also How Stuff Works

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Re: 1590: "The Source"

Postby Keyman » Thu Oct 15, 2015 6:20 pm UTC

Shamino wrote:
Wee Red Bird wrote:Arrrgh, its early in the morning, still a little dark outside, and a florescent tube above my desk is doing that 'plink plink' noise with a bit of humming in between. Throw in the disco strobe effect and I'm about to crack. Aaarrrrggghhhhh. If it wasn't behind a plastic sheet I'd take the bloody thing out with my mug.
Something in the fixture is worn out and needs to be replaced.

The plink-hum is the starter repeatedly trying and failing to strike an arc that will create the plasma needed to light the bulb. If you can see the starter itself, you will probably see a light glowing from inside it. Once the arc is struck and the bulb remains lit, the starter will stop trying to light the bulb and the noise will stop.

To fix the problem, start with the easiest solution - replace the bulb. If that doesn't work, replace the starter (assuming your fixture is an old enough design such that it has a replaceable starter.) If that doesn't work, you'll probably have to replace the ballast. Replacing a ballast can be a pain in the neck - it's often cheaper and easier to just replace the fixture instead.

See also How Stuff Works

Or just replace it with an incande....
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Re: 1590: "The Source"

Postby ucim » Thu Oct 15, 2015 11:09 pm UTC

orthogon wrote:Well, ok, you can have a high-pitched hum in the same way that Hiroshima was hit by a small atom bomb, which is to say relatively speaking.
Hiroshima was hit by a small atom bomb. It just wasn't hit by a small bomb, of the atomic variety. :)

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Re: 1590: "The Source"

Postby RogueCynic » Fri Oct 16, 2015 3:17 am UTC

deskjethp wrote:
Znirk wrote:My office has an HPHG, but it's labeled as an HP Laserjet M551.


Typical HP printers. They aren't to be trusted.

I had an HP 3055 printer/copier in my office. It ran (presumably) quite a few years before I got the job and two years later. It was so old we could not find toner in our ordering system. It died and we replaced it. After about a month, the replacement started printing black pages when copying. We replaced it with a Lexmark. The Lexmark freezes my pc when I reboot, something to do with incompatible firmware. I miss the 3055.
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Re: 1590: "The Source"

Postby Morgan Wick » Fri Oct 16, 2015 3:30 am UTC

My reaction to reading the comic: I'm guessing this is a reference to a game or movie or something, or maybe to a common trope in certain types of games or movies.

ITT: Absolutely zero reference to whatever it might be a reference to, except for one guy who inquires about what it might be about and gets linked to a completely irrelevant xkcd, and instead a lot of talk about real-life high-pitched hums.

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Re: 1590: "The Source"

Postby Pfhorrest » Fri Oct 16, 2015 3:54 am UTC

Morgan, I think the only joke here is imagining that the annoying high-pitched hums a lot of us deal with in our lives aren't coming from any specific piece of useful machinery, but are just being pointlessly generated by a high-pitched hum generator in the basement, that you could just as well go and turn off.
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Re: 1590: "The Source"

Postby RealGrouchy » Fri Oct 16, 2015 4:26 am UTC

1. I once had the situation displayed in the comic while sitting in my living room, except it was a beeping. Investigation eventually determined it was an alarm clock in the second floor apartment of a neighbour across the street*.

2. My next door neighbour installed a natural gas connection a year or so ago, and the exhaust pipe that empties into the shared narrow alley emits sounds that are unnoticeable when you're next to it, but inside the house the walls strip out all but a high-pitched whistle. Pain in the ass. (Since the sound was from air coming out of a pipe, it was indeed a whistle)

3. My apartment is in the same (old woodframe) building as a restaurant, and when their exhaust fans bearings got out of alignment it vibrated my entire living room and bedroom, but almost none of the rest of the building. The restaurant owner didn't understand that the sound I was complaining about was caused by the sympathetic vibrations in my living room. He assumed that sound had to travel in a direct line (through the walls as easily as through the air!) and since he didn't hear the fan he didn't believe me until I harassed him into fixing it.

*Imagine how fun my life is, with the combination of very sensitive hearing and being very bothered by miscellaneous noises. I have difficulty hearing people speaking because I hear everything else just as loud.

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Re: 1590: "The Source"

Postby yyy » Fri Oct 16, 2015 5:53 am UTC

Morgan Wick wrote:My reaction to reading the comic: I'm guessing this is a reference to a game or movie or something, or maybe to a common trope in certain types of games or movies.

ITT: Absolutely zero reference to whatever it might be a reference to, except for one guy who inquires about what it might be about and gets linked to a completely irrelevant xkcd, and instead a lot of talk about real-life high-pitched hums.


yyy wrote:The generator is activated by reading randomly named scrolls.


To clarify:

Spoiler:
It is a reference to rogue, where reading the aggravate monsters scroll causes:

You hear a high-pitched humming noise.


That humming noise aggravates monsters causing them to chase you.

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Re: 1590: "The Source"

Postby CharlieP » Fri Oct 16, 2015 8:29 am UTC

ucim wrote:
orthogon wrote:Well, ok, you can have a high-pitched hum in the same way that Hiroshima was hit by a small atom bomb, which is to say relatively speaking.
Hiroshima was hit by a small atom bomb. It just wasn't hit by a small bomb, of the atomic variety. :)

Jose


I'd say Uranium-235 was pretty large atoms, by comparison to most others.
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Re: 1590: "The Source"

Postby The Moomin » Fri Oct 16, 2015 9:11 am UTC

CharlieP wrote:
ucim wrote:
orthogon wrote:Well, ok, you can have a high-pitched hum in the same way that Hiroshima was hit by a small atom bomb, which is to say relatively speaking.
Hiroshima was hit by a small atom bomb. It just wasn't hit by a small bomb, of the atomic variety. :)

Jose


I'd say Uranium-235 was pretty large atoms, by comparison to most others.


Uranium-235 is teeny compared to the Ariel Atom

In a review, the supercharger was noted to have a space-aged wail rather than a hum, whine or whistle though.
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Re: 1590: "The Source"

Postby Neil_Boekend » Fri Oct 16, 2015 10:57 am UTC

hamjudo wrote:
Spoiler:
Neil_Boekend wrote:The amount of power used by a normal house running at 30 KHz? It would have certain advantages: No batteries in the remote anymore, since the power requirements for a remote can easily be picked up out of the air. Same with the smoke alarms and many other battery operated devices. They could just have a coil and a capacitor, tuned to 30 kHz.
It would bug the hell out of the "Electromagnetic radiation is bad" crowd though. And many metal objects would get hot, especially with a length of 5 meters (1/2 λ). Such as steel structural elements of your building. All that heat would be loss (doubly so in the summer with the airco on.).


You're not taking this thought experiment seriously. You got the implied part about replacing all of the motors, transformers, circuit breakers, and power supplies, but missed the implied part about replacing all of the wiring.

Back in 1981 or 82, I took a physics course which covered the theory of this stuff in extreme detail. Alas, I did not retain it. Thus forcing me to ask a question where I should know the answer, but I don't. Would twisted pair wiring be sufficient with 30Khz power, or would we need to use coaxial cable?

I've got a copy of the National Electrical Code Handbook, from 1993. It is a thick book (about 6 cm). Most of the rules in the handbook were created after multiple fires, injuries, and/or deaths. I'm sure the current version is even thicker, given that there have been a couple more decades of fires, injuries, and deaths since that book was written. Adding rules for 30Khz wiring would probably make it a 10 cm book, plus require a whole bunch of fires, injuries, and deaths.

Obviously, the right thing to do, is to skip high frequency AC power, and get prepared for high voltage DC power. High voltage DC power transmission lines are already cost effective in a few situations. If the power line is superconducting, DC is the only way to go. Superconducting lines are much smaller per megawatt, than equivalent AC power lines (even with the added space for the cryogenics). So it is often cheaper to go superconducting, than to make a tunnel bigger.

DC power lines are smaller if made out of plain old aluminum or copper, but they still require a lot of space and money for the equipment to convert from AC to DC and vice versa. It makes sense for very long terrestrial power lines, and for comparatively shorter lines that need to be buried beneath a body of water. It is an absolute requirement for power lines that connect grids that aren't synchronized.

The conversion equipment is getting cheaper, smaller, and more reliable over time. So high voltage DC transmission will eventually become cost effective for the power lines that connect substations. After conversion equipment becomes cheaper than transformers for individual houses, we will see DC power to the meter. Then, running DC power within houses will start to make sense.

I expect the walls of my grandchildren's houses will have DC outlets. At that point DC to legacy AC adapters should be very efficient, small, and inexpensive.

Also, the National Electrical Code already has safety rules for DC, so we won't need a new set of fires, injuries, and deaths. Although, I'm sure there will be quite a few as high voltage DC use scales up. Hopefully, there will be less than if we stayed on AC.

Now is the time to lobby standards bodies, and legislatures for acoustic limits for power conversion equipment. Many current DC-DC converters emit high pitched whines. That should not be allowed. We will have the technology.

Indeed I wasn't taking it seriously.

HVDC only has specific uses. That is mainly the HV part, as 500KV is not something I would advise in a regular house. Keeping a distance of 5 meters between yourself and a wall socket at all times is not feasible. There is a good reason why only long distance lines are HVDC and it is not technological. It is because high voltage is incredibly dangerous. You are talking about lines that do this if you switch them (at the end of the clip the camera pans to a man, use it for scale). Don't get close to those.
They make them at these high voltages despite the safety issues because of losses. A cable through which a current runs gets warm. That heat is all loss in this case. More current is more heat is more loss. You can combat this by making the cable diameter bigger but then you have to have massive cables, and that is not feasible for extremely long lines.
So you want to keep the current down. Power is current times voltage. Ergo, if you want to transmit 500,000,000 W (500 MW), and have a voltage of 110V you have a current of 4,545,454 A. Four and a half million amps. That would require cables of (guestimate) 100 meters in diameter. Those cable diameters are not possible.
However, if you convert it to 100 KV you have a current of 5000 A. Much better. You still need a thick cable but these are at least possible.
So long high power lines get high voltages to make it possible to build them at all. In fact, most long distance powerlines are as high as can be done safely at the time and place it was constructed.
For long distance lines that can be up to 750 KV.
That is why they use high voltage. And they use it despite the safety issues. With training of your people, fences around equipment and sufficient height for your power lines the safety issues are manageable.
You can't train everyone to work with 500KV.

The DC part of HVDC is due to synchronisation issues. You have to convert to DC at some point anyway when connecting two separate nets (like, for example the US eastern and the US western net), since you can't just connect two or more 50 or 60 Hz main nets with different phases and not expect your equipment to blow up. Timing issues make it better to have the long line DC. It doesn't make much difference safety-wise.

DC is in fact used in houses, as I guess you know. Modern wall wart transformers already convert to DC, then to a high frequency (for example 30KHz), then to the right voltage (with a small but efficient 30KHz transformer) and back to DC again.
DC on the house net doesn't matter much, safety wise. There are two ways to do this: either convert to DC between the net and your house or switch the full net to DC. Either way most of the current equipment you have would be useless, since it is designed for 50 or 60 Hz AC.
With the conversion between the net and the house a converter would have to be installed. Costs probably $1K (guestimate) a piece in sufficient quantities. That converter can die, leaving your house powerless.
The better solution would be to switch the net to DC. The problem then is that current main net transformers (varying from thousands beasts of several tonnes with a significant price tag to probably close to a million smaller sub one tonne transformers) are made for 50 (or 60) Hz. Thus all the current transformers would be outdated. Billions of dollars of installed base would be outdated.

Also, your problem wouldn't be solved. You wouldn't get rid of the conversions. Different equipment works at different voltages. You can't charge a phone at the same voltage a washing machine requires to operate without a DC-DC transformer. And that DC-DC transformer could still whine. The part in a modern transformer that wines is NOT the AC/DC conversion. It is the DC-High frequency AC-High frequency AC (different voltage)-DC conversion set that whines.

As for 30 KHz: The equipment would be outdated too. Additionally coaxial cable costs or inductive losses would rule out long distance on that frequency. Thus the switch would have to be done at the neighborhood or house level. There are many neighborhood level transformers, all would have to be replaced. Billions and billions for the US alone.
Mikeski wrote:A "What If" update is never late. Nor is it early. It is posted precisely when it should be.

patzer's signature wrote:
flicky1991 wrote:I'm being quoted too much!

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cellocgw
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Re: 1590: "The Source"

Postby cellocgw » Fri Oct 16, 2015 11:34 am UTC

CharlieP wrote:
ucim wrote:Hiroshima was hit by a small atom bomb. It just wasn't hit by a small bomb, of the atomic variety. :)

Jose


I'd say Uranium-235 was pretty large atoms, by comparison to most others.


Which is why we need to train people in the use of the hyphen :P At least AFAIK it hasn't been renamed "the Oxford hyphen" yet.
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kytau
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Re: 1590: "The Source"

Postby kytau » Fri Oct 16, 2015 10:13 pm UTC

Did it occur to anyone else that the high pitched hum generator might be a metaphor for What If? Maybe it has become an annoyance to Randall and he is finally pulling the plug....

Maybe I am looking into it too much...

xtifr
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Re: 1590: "The Source"

Postby xtifr » Sat Oct 17, 2015 6:29 am UTC

cellocgw wrote:
CharlieP wrote:
ucim wrote:Hiroshima was hit by a small atom bomb. It just wasn't hit by a small bomb, of the atomic variety. :)

Jose


I'd say Uranium-235 was pretty large atoms, by comparison to most others.


Which is why we need to train people in the use of the hyphen :P At least AFAIK it hasn't been renamed "the Oxford hyphen" yet.

So a small-atom bomb results in a really big-ass explosion, while a small atom-bomb merely results in a big ass-explosion.

I've got that right, don't I? :D
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