Airport problem when connecting external display

I have a Macbook Air running 10.5 and I am having an issue with the internet connection slowing down every time I use my TV (50" plasma 1080p) as a monitor. The wireless internet connection either slows down or stalls out completely. The moment I disconnect it from the TV, everything starts working again, full speed. I have already moved my wireless to another room because I thought the TV might be interfering with the connection but that didn't help at all. Any help is appreciated.

It sure sounds like the TV is somehow interfering with the wireless signal. Try going into your router and change the channel your wireless signal is being broadcast on. If that doesn't help, try another router if possible.

Regards.

Does your internet slow down while you're using another monitor AND the HDTV is on from another source? If it's RF interference, the slow down should occur whenever the TV is on. If not, then I'd suspect the Mac is having trouble outputting to the 50" TV. Try changing the resolution.

I have this same problem! I am very new to Mac, this MacBook pro being my first and only got it about 3 weeks ago...

It does not happen all the time, but it happens more often than not....
When I connect my Samsung 24" external display, my internet connection just goes out. Once I remove the monitor, the internet comes back... I am working with the MacBook open, and the displays configured as one large desktop. Like I said, sometimes it works just fine, but more often than not there is a problem...

I have seen where someone mentions to change the channel of the router, but I don't know how to do that either.. I have a basic Netgear Router, and I don't see any "channel" switches...

sorry for my ignorance, could someone please help!

Do you have a manual that came with your Netgear router? If I remember correctly, Netgear provides a setup CD with their routers. The setup CD has a manual in PDF format that you can read or print out.

Also, you will need to know how to access your router's setup menu from your computer. Make sure you have an ethernet cable that you can attach from the Netgear to your computer before making any adjustments.

Regards.