OK, so in my mind the span between peak and trough of a full wave is 220, a half wave is 110 to zero.
It makes sense your statement on insulation, but the power…
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Damnit…
so 110 peak to zero with a break vs two lobes of 55v peak…
With the 30 lost lobes/sec only double total heating 400 upped to 800 watt power but much harder knocks onto the system with the thermostat reaching its cutoff faster and probably higher risk of blowing the thermal safety fuse.
Needs a resistor inline to drop to proper wattage.
Thinking back now, it was mostly floating ground issues and RF not really touching live mains wires.
There are a couple little issues here. First, we have the concept of RMS. The mains power is a sine wave (should be, at least, but you can get some quite dirty power and then get oddly dying devices or weird malfunctions that are specific to that one apartment or house and stop happening once you move the stuff elsewhere; if things are odd, stick the scope to the socket.)
For sinewave, the zero-to-peak is a sqrt(2) of the RMS value. In case of 220V it is 311 volts. (A capacitor fed with a diode will charge to this value. One of the little things to be wary of.)
With RMS value, you can approximate the power as DC. Therefore the 311V-peak sine wave will give you the same power to a resistive load as a 220V-peak square wave.
If you take away half of the waveform, you take away half of the dissipated power. You effectively introduce a PWM regulation with 50% duty cycle. So half the power it is.
As by doubling the voltage you quadruple the power, by doubling the voltage and halving the power you still get twice the power.
Or two identical toasters in series instead of one. Then you have 110 volts on each, and they are within specs. (Or take them apart and if you have pairs of heaters in parallel, connect them in series instead.)
The previous owners of my house (in Canada) were immigrants from the UK. One of the daughters was an avid sewer (I believe she ended up going to college for fashion design, or something), and had a VERY expensive sewing machine from the UK that she wanted to use here. So her parents had an electrician come in and add a 220v outlet in the basement (with a regular North American plug - she just used a plug adapter to use the sewing machine). So now we have a 220v outlet in the basement if we ever want to use it for… Something. My wife has a hair straightener from Ireland that I’m sure she’d enjoy using, but she can’t be bothered going down to the basement to use it 
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Oh, and for those of you not in the contiguous 48 who would also like to use non-Keurig cups (like, for example, one of the reusable ones) and can’t get one of these shipped to you… If you have a piece of tape and one Keurig branded cup, you can use this method
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[imagine shoop of a french press with a file in it here]
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Given Obi-wan’s description, I am not sure I would want to use a toilet or a Keurig at Mos Eisley spaceport.
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Time consuming? I have a small espresso machine. Making a cup of coffee takes about 2 minutes from the moment I switch it on.
Choice? Obviously the new word for quality in our time.
Taste not necessarily makes waste ^^
Not everyone wants to deal with coffee grounds. Having them packed away in a throwaway cup can be quite an advantage, hassle- and logistics-wise.
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Mmmm… Instant Coffee… 
As someone who enjoys making coffee by grinding beans, and putting them into an inverted aeropress, I have noticed that k cups have occupied much of the shelf space formerly given over to whole bean coffee. The kcup fad expands other’s choices, while impinging on mine.
I love how they have an American flag watermarked in the background of the banner at the top of the page, as if to say, ‘Circumvent coffee DRM. It’s the American way.’
I was wondering if they could create a pattern with the ink that could be copyrighted…
Edit: I guess that would require a more expensive sensor.
Yes. But copying that copyrighted art would likely be fair use.
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Because I once remember someone offering an explanation very similar to yours. It’s OK, regard it as a compliment.
In fact the peak voltage for 110VAC is around 170V (allowing for fluctuations), and for European 230VAC is around 350V (also allowing for the tolerance.) If you use the correct rectifier layout with a couple of capacitors, you get 700V DC from 230V mains.
What is worse (and this goes back to work I did years ago on lightning protection) is what happens when lightning strikes overhead lines. This can cause considerably larger peaks downstream. European domestic electrical systems are actually designed to insulate against over 2kV, but if the same unit contains mains power and a user accessible socket such as a headphone socket, much heavier insulation is required. This was one reason for the now ubiquitous power brick, as a mains charged phone or laptop needs a certain thickness to allow for that enhanced insulation. (Amusing, to me, note: when we were doing this work we needed a fast amplifier that could withstand 10 000V between its inputs and outputs. After placing the order, I got a phone call from the US Embassy asking what we wanted it for. I guess orders for these things were always checked and someone had noticed we also had radioactives on site. I was able to reassure him we were not making bombs.)
The control systems on domestic appliances that someone mentions above are the devil incarnate. They actually comply with standards but use air gap for insulation so there are exposed live prongs. On the rare occasions I have looked into one, I have always used a probe ending in a rubber insulated croc clip, which is earthed the other side of either a neon bulb or a pen-type voltmeter. Perhaps the object was to reduce the number of electricians brave enough to get into those things and (returning to topic) encourage people to replace rather than fix.
Not really a precedent. The watches were all manufactured by the company authorized to use the trademarked image. They weren’t knock-offs.
In my example, the use of a trademarked corporate logo as the unlock pattern, the fair-use argument wouldn’t hold water. It would be difficult to argue that putting another company’s logo on a very similar product, in the exact same location, doesn’t cause product confusion for the public, which is the legal test of trademark infringement.
Actually, it was a copyright case not a trademark case. Oyster placed a copyrighted image on the back of the watch so that they could claim copyright on the watch and tried to govern the importation of the watches under copyright law. The court found that copyright law could not be used to do what other laws could not in preventing the grey market resale watches.
It is a tangential case however it shows that copyright is not designed to be stretched into a purpose for which it is not intended.
