K3 battery time worse when using 3G and wifi?

[Tiersten]

Originally Posted by TomF

With the Kindle 3G (Wi-Fi & 3G), when you turn wireless on it will search for a previously set up Wi-Fi connection. If it finds one, it will turn 3G off and use the Wi-Fi connection. If it doesn't find one it will leave 3G on. You can't explicitly turn on one or the other and you can't explicitly turn off one or the other. If wireless is turned off, both 3G and Wi-Fi are turned off.

Nope. The Kindle 3G+WiFi is still connected via the cell modem even if you're using WiFi. It doesn't disable or turn off the modem when you're using WiFi. You can check yourself if you look at one of the settings info pages 611 or 711 I can't remember and my Kindle isn't handy to check. You'll see the cell connection is still active and is connected via 3G/2.5G data.

[Tiersten]

Originally Posted by twister

Another thing I have noticed with K3 is that it says EDGE instead of 3G which is on my K2. Is my K2 also on EDGE but lists it as 3G? I wonder if EDGE eats up more battery than 3G...

"3G" isn't a specific standard as it just means 3rd Generation. It is two things. A label which defines what generation of cellular standards a device supports and a marketing term. The two don't quite match up properly.

EDGE is technically a 3G standard according to the standards body that regulates these things but from a marketing point of view, it has been advertised as 2.75G and 3G.

It is similar to how "broadband" or "high speed internet" can mean a wide variety of speeds and technologies. How fast a connection needs to be to qualify as broadband or highspeed internet depends on where you are.

As for whether a K2i (Only the K2i can support EDGE. The K2 can't do it as it isn't GSM) will show EDGE as 3G I'm unsure.

[hellraiser06]

Okay, I read up on Amazon that if 3G is not available, the Kindle 3 will fall back on EDGE/GPRS. This consumes more battery than running on 3G. This information is on Amazon.

Quote from Amazon:
Long Battery Life - Up to a Month

Battery Life of Up to One Month
A single charge lasts up to one month with wireless off. Keep wireless always on and it lasts for up to ten days. Battery life will vary based on wireless usage, such as shopping the Kindle Store, web browsing, and downloading content. In low-coverage areas or in EDGE/GPRS-only coverage, wireless usage will consume battery power more quickly.

And this is what it says fro Kindle Wifi:
Long Battery Life - Up to a Month

Battery Life of Up to One Month
A single charge lasts up to one month with wireless off. Keep wireless always on and it lasts for up to 3 weeks. Battery life will vary based on wireless usage, such as shopping the Kindle Store, web browsing, and downloading content.

Now, if you have a 3g K3, then it clearly says, that the battery life is UPTO 10 days. With the wifi K3, the battery is rated at 3 weeks with Wifi on. From this, what I deduce is that the 3g part (cellular part) of wireless is the one that consumes the major chunk of the battery. Now, that is if you just leave the wifi on and do NOTHING on it. If you are obviously browsing, then you will get less battery life. In my opinion, what you are getting is perfectly fine. Enjoy your Kindle. To save battery, turn Wifi off, when not needed.

Now, if you are interested in some technical gibberish, let me explain something. When you have a device capable of running on different standards (in this case, 3G and Edge/GPRS), the standard that was developed earlier would drain more battery. Its true with every device.

For further reading
http://en.wikipedia.org/wiki/3G

[TomF]

Originally Posted by Tiersten

Nope. The Kindle 3G+WiFi is still connected via the cell modem even if you're using WiFi. It doesn't disable or turn off the modem when you're using WiFi. You can check yourself if you look at one of the settings info pages 611 or 711 I can't remember and my Kindle isn't handy to check. You'll see the cell connection is still active and is connected via 3G/2.5G data.

I was going by what Amazon states in the User's Guide:

PDF, p. 39, 2nd par., or location 464
"Your Kindle automatically turns 3G coverage off when you connect using Wi-Fi. If you disconnect from a Wi-Fi network or if you move out of Wi-Fi range, Kindle automatically switches back to 3G coverage. If you want to turn off 3G coverage, you can turn Whispernet off. Keep in mind that turning Whispernet off also disables Wi-Fi connections."

[Tiersten]

Originally Posted by TomF

I was going by what Amazon states in the User's Guide:

PDF, p. 39, 2nd par., or location 464
"Your Kindle automatically turns 3G coverage off when you connect using Wi-Fi. If you disconnect from a Wi-Fi network or if you move out of Wi-Fi range, Kindle automatically switches back to 3G coverage. If you want to turn off 3G coverage, you can turn Whispernet off. Keep in mind that turning Whispernet off also disables Wi-Fi connections."

Yes. It is worded poorly and may be an implementation issue but currently it just means that they're connecting to Whispernet via WiFi instead of 3G. They're not actually turning off the cell modem. Go to Settings and then type 611 (Alt + YQQ) to get to the cell modem info page and you'll see it is still connected.

The reverse is also true. You can be connected via 3G but the WiFi interface will always be on and searching for hotspots or access points.