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Apple Acknowledges iPad Wi-Fi Issues, Sort Of

As Glenn wrote in "Some iPad Users Suffer Wi-Fi Woes" (6 April 2010), some iPad users (including me!) have experienced problems with Wi-Fi connectivity. These problems generally revolve around unexpectedly poor Wi-Fi signal strength, frequent Wi-Fi network dropoffs, widely varying network throughput, and repeated requests for Wi-Fi network passwords for remembered networks.

Apple has quietly updated a Knowledge Base article about issues that iPads have when connecting to Wi-Fi networks. Initially, the article offered only basic suggestions, like making sure your Wi-Fi router's firmware was up to date, and using WPA or WPA2 instead of WEP. While I'm sure using current firmware and modern encryption approaches are a good idea, they really weren't related to most of the problems.

In the updated article, Apple now suggests that having the screen brightness at its lowest setting could be related, which sounds truly weird. However, commenter Eugen notes that common methods of dimming LEDs could result in oscillations that could interfere with other radiation, such as Wi-Fi signals. And I've heard from a reader that raising the screen brightness on his iPad did indeed solve his particular Wi-Fi connection problem.

Apple has also lumped the iPad DHCP flaw into this article about Wi-Fi connectivity issues, even though the two problems are almost certainly unrelated (see "Princeton University Identifies iPad DHCP Flaw," 15 April 2010). Apple suggests renewing the DHCP lease manually, or toggling Wi-Fi off and on again, both of which should help if the iPad itself isn't working properly, but which won't solve the general problem of duplicate IP addresses for other devices. Princeton's workaround is more general, and should prevent the problem from occurring.

In fact, the most heartening change to the Knowledge Base article is this sentence at the top.

"Apple will also address remaining Wi-Fi connectivity issues with a future iPad software update."

That's exactly what we thought would be necessary, and here's hoping that we see iPhone OS 3.2.1 for the iPad soon, complete with fixes for both the Wi-Fi connectivity problems and the DHCP flaw.


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Comments about Apple Acknowledges iPad Wi-Fi Issues, Sort Of
(Comments are closed.)

"In the updated article, Apple now suggests that having the screen brightness at its lowest setting could be related, which sounds truly weird. If anything, it would seem that having the screen brightness high would be more likely to cause interference with Wi-Fi"

It is little known that to decrease the brightness of an LED decreasing the voltage is not a good idea. The emitted light spectrum would change, resulting in changed a color representation (probably warmer ).

To decrease the light emitted by an LED, a common method is to turn it of for a fraction of a second. This way the color doesn't change and the eye usually doesn't notice that the LED is turned of for a small amount of time, since it averages over a larger time-span. This also limits the minimum brightness, since at some point flickering will occur.

To get back to the discussion above, turning an electronic device off and on very often results in oscillations and can interfere with other radiation.
Adam Engst  An apple icon for a TidBITS Staffer 2010-05-12 11:04
Oh, that's fascinating... I'll have to look into that more.
Bob Peterson  2010-05-12 12:02
A software update might simply limit how dim the iPad can become. Would that affect the battery life?
It's not necessarily the lowest brightness setting affecting the wifi signal, but could also be the 2nd lowest etc. I don't know how large the frequency range emmited by the screen is, but if it's narrow one option could be to just allow different brightness levels than currently via firmware. If the range is broad and interference occurs at the lowest brightness levels, increasing the lowest brightness is an option. The screen takes usually 2/3 of the power and the consumed power is proportional to the brightness level.

Of note should also be that wifi has different channels available, tranitting at slightly different frequencies. Thus changing the channel could increase signal strength in this case. Also 3G signals should be unaffacted due to different transmission frequencies.
"The screen takes usually 2/3 of the power and the consumed power is proportional to the brightness level."

If Apple releases "iPad Junior" with a 6" screen, as rumored, how much less power would it consume? And would that affect receptivity? (And wouldn't the weight be less than half the current iPad?)
Motorcycle Michael  2010-05-19 08:55
The iPod Touch has long suffered this same connectivity issue - can't find known network (when other devices do), repeated/rejected requests for password, etc. - rare, illogical, but there are discussions online going back to 2nd iPod Touch model. Mine still does it occassionally - charging seems to matter.... why?
alandoland  2010-05-31 21:36
Tasks that support start dates as well as due dates and which use contexts and projects [like they are used in Pocket Informant and OmniFocus] would be nice too, especially if they are synced to the extensible mcpd Sync Services so that they could be synced with the two applications mentioned above.