iMac Wifi issues.... Going insane. PLEASE help/input

From reading your diagnostic steps, I think you were insane before your wifi issues.

 

Have you tried running WiFi Diagnostics?

 

Is your network password protected?
Did you use the same SSID or a new one in recreating the network?

One of the problems seems to have to do with keychain corruption.

 

Don't understand your reply. WiFi Diagnostics is part of Lion Core Services and might help you troubleshoot your issue. It's a program you run.

 

I've never used the tool to troubleshoot a problem, but from what I have seen using it on a working system, the logging feature seems like it would show error or exceptional conditions if one is having wifi issues.

Maybe we can both learn something here!

 

That is an ugly chart. I ran the performance monitor on my system and the signal was a nearly constant -37 and the noise a nearly constant -90. Your signal fluctuations make me wonder if you've got interference.

 

Here is my chart.

 

I'm wondering now if your chart is illustrative of a bad wifi card. If we assume your router is putting out a good wifi signal (because your iPhone and iPad connectivity is good), then maybe what this chart shows is a wifi card that is not receiving a constant signal. That could explain the dropped connections.

 

Too many variables to figure out still. You need to start eliminating some....

Start simple, and work to more complicated steps.

First... connect your iMac to the router with an ethernet cord.... If it still drops out then it's not Wifi, it's something else.

Then swap out the router for known working one. If it still drops out, it's not the router.

Are you on ADSL? Has someone removed the noise filter? Is the land-line telephone still firmly connected. In fact, unplug all the phones. Is it still dropping out? If not... problem may be with the phones.

Are the phones cordless? Unplug them and check. If the dropouts continue, plug them in one by one.

Have you changed Wifi channels? A neighbour may have installed something new.

Are you sure the internet connection from your house to the ISP is clean? Phone and and iPads don't really tax the connection the way a computer can. Plug a borrowed computer directly into the modem, and see do one of the speed checks. See if the connection speed is what you expect. If not, it's modem or ISP issues.

Your issue sounds, incidentally, just like a friend of mine. She was going mad with dropouts, even though her daughter's iPhone was fine. The phone company (ISP) finally sent someone who checked everything and said that actually they were aware of an issue in their switching office. She was pretty mad because she had been talking to phone support who had her doing all sorts of gymnastics (both virtual and actual) - though they knew it was in their offices.

In my experience, start with the easy stuff... and then assume it's the ISP's fault. If you can't eliminate the ISP as the source of the problem, then start with your own setup.

Luck.

 

I was going to suggest something like that. I would agree all things point to a bad card if the problem is repeated at your friends house.

BTW, iMacs are great until you have to lug them around.

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Don't forget to take your ugly chart with you ... and maybe a copy of mine too.

 

If the beginning of your issues.....

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