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American netbook in Japan. 2010/9/8 00:55
United States
My question is about if I where to bring an American Net-book that I bought in the States, would it work in Japan?
by mrkc  

voltages, plug , and internet connection 2010/9/8 16:04
I guess you have a few issues...voltages, plug , and internet connection.

Japan mains supply is 100volts and US is more (120volts I think?) So assuming your netbook requires more than 100V you will need a STEP UP transformer, dont confuse it with the more common ''STEP DOWN'' transformers. Any electrical store can help you. Just check beforehand on your product to see what voltage it needs. explain to them in terms of voltage in (100V-Japan mains socket) and voltage out (?V whatever you need- check device)

I think you need a plug adapter. not difficult to find in electrical store. US to JP type

There are of course many ways to connect to the internet this depends on a lot of factors like will you be using it in your home? a hotel? does it need to be used anywhere like on a train? how long are you in Japan? do you live here or just for short term use?
by gilesdesign rate this post as useful

... 2010/9/8 17:27
Every decent laptop these days comes with a built in voltage transformer that supports the world's voltages (the black box on the electric cable). So, voltage should be no problem.

The Japanese plug is similar to the North American, as explained here:

Internet connections (LAN cabel and wireless LAN) work the same as in the US. Getting a subscription for a wireless LAN service can prove more difficult, though.
by Uji rate this post as useful

no transformer needed 2010/9/8 17:35
I have used my Japan-purchased laptop in New Zealand, where the voltage is 240V, and the built-in transformer worked fine. As Uji says, There is no need to buy a transformer for any computer purchased in about the last 10 years, transformers are built in.
by Sira (guest) rate this post as useful

check the voltages on the product 2010/9/8 18:29
Sorry maybe you don't need a step up transformer I don't know much about US and Japan compatability but as I said check your device if says it runs on just 100v then it will be fine.

Always check the voltages! they should be written carefully on the product!

those little transformer boxes dont just magically convert any input voltage to any output voltage.There are many types read exactly what they convert from what to what.

I have various appliances from UK that I brought to Japan that DO NOT work. Even with the transformer boxes included with the power cable. Even if it is a new product you cant run something off just a 100v if it needs more than 100v.

Similarly, a MUJI store radio my sister bought in Japan blew up with smoke and sparks when she plugged it into the 240V socket in the UK. And that included a little which box transformer but it cant receive voltages of 100v not 240v.

I use a step up voltage transformer to power a B&O stereo that simply cant run on Japans weak voltage. (the step up transformer is a heavy box - its very different to to the standard little step down types included with products you see all the time)
by gilesdesign rate this post as useful

electronics 2010/9/8 19:30
Lots of appliances certainly do need transformers- it would be pretty surprising if a Muji radio didn't need one, for example, but things like laptops and camera chargers come with transformers as standard these days. I wouldn't assume most electronics had built-in transformers, but with a laptop or netbook or digital camera you can be certain that they do- basically they are manufactured with international travel in mind.
by Sira (guest) rate this post as useful

My five cents 2010/9/8 20:22
Actually transformers (the big and bulky ones) in power cords are nowadays not used and for sure not in modern netbooks. They are 'switchin power supplies'. I Know this is technically. The only thing you need to do is check on the adapter (either in the power plug or as a black box in the power cord) what the operating voltage range is. Most modern devices (except bought in Japan!) work on 100-240V and the frequency is not important (unless you want to use it in an aircraft). If your adapter says 100V it is OK to use in Japan. If it says 110-130 V i am pretty sure it still works (maybe do not charge the battery and use the netbook at the same time). In the latter case i would give it a try. For sure i would not carry a heavy step-up transfer (unless it is a modern type with a switching step-up power supply). As alternative you might consider to buy an universal laptop powersupply ($25-50) at the local computer store at home or in Japan.
The 2 sprong powerplug are the same in the Japan as in the US. You might consider to bring an extension cord with multiple sockets because sometimes the number of outlets in a hotelroom is limited or at the wrong place.
The LAN and WLAN (WiFi) are the same in Japan as in the US so this should not give a problem (as was mentioned above).
Have a nice trip
by B. Slager (guest) rate this post as useful

transformers 2010/9/8 20:43
"I use a step up voltage transformer to power a B&O stereo that simply cant run on Japans weak voltage. (the step up transformer is a heavy box - its very different to to the standard little step down types included with products you see all the time)"

There seems to be a lot of confusion about terminology.
The small power supplies you get with just about any device such as laptop computers, mobile phones, small radios, chargers, etc are not called "Step down transformers".

These are called power supplies. Yes, they DO change the voltage from 100-240V AC(Alternating Current), down to 5V, or 3.7V, etc. These provide DC (Direct Current) to the device. There are two types: one with transformers, and "switch mode". Generally, the light "switch mode" power supplies can have a supply voltage of 100-240V AC, while the heavier transformer types don't.

Your B&O stereo obviously runs on 240V AC, and you need a step up transformer to transform 100V AC in Japan to 240V AC for your B&O. Conversely, If you have a device like your sister's that was bought in Japan and only runs on 100V AC, you need a step down transformer to convert 240V AC to 100V AC back in the UK.

"Step up" and "step down" are essentially identical, but used in reverse. If your device uses a lot of power (like your stereo) it will be big. It it uses very little power, it can be very small.

by Sandy (guest) rate this post as useful

thanks for the clarification 2010/9/9 12:36
thanks for the clarification...about terminology.
"step up" and "step down" was my easy way of describing something that increases voltage and something that decreases voltage. (the point being that both directions exist not a magic box)
Anyone know why does Japan have only 100v? It seems the weakest voltage of any country in the world! Is it a safety thing because dont have earth on plugs or something?
by gilesdesign rate this post as useful

Main power differences 2010/9/9 14:38
The logical explanation is that the average distance from the last transformer station to consumers house is very different.

For example, in Japan the distance is low, and so a mere 100V is fine. In Sweden however, the distance could be many tens of kilometers, and so using an industrial level power supply (230V) means we lose less energy in the transmission.

The actual reason is probably just an arbitrary political decision based on what was already existing in the country though...
by Hokan rate this post as useful

no problems here 2010/9/10 16:36
I've been using a US-made laptop in Japan for 6 years with no problems with voltage or whatever. I did however have to get the 3-prong to 2-prong adapter so I could plug in my charger. I know very little of electronics and this might be the adapter/converter people mention, but it only cost me 300 yen at a elec shop vs. the real "converters" I saw back home that cost a lot more.
by jmarkley rate this post as useful

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