Sorry for being slightly off topic, but...

It's been mentioned in the past that those old Look-TV antennas cannot be used for OTA, which is understandable.

However, I was looking to build a WiFi biquad dish antenna (http://www.engadget.com/2005/11/15/how-to-build-a-wifi-biquad-dish-antenna/) to enhance my wireless signal, when I realized that I still had an old Look TV antenna. I understand that Look TV broadcasted in the 2.5 - 2.7 GHz range. Would this be a suitable antenna for standard WiFi ?

Wifi b/g is 2.4 ghz, so yes.

Whats the distance youre looking for ?

About 350 meters with obstructions. Not sure if this is really possible, but I've read about some folks getting wifi signals over a few miles with the biquads.

seriously,

i can't wait to see the results as i have one kicking around mom and dads

cheers

About 350 meters with obstructions.
350 meters isnt a problem with higher gain antennas, but the obstructions are. You really need a clean line of sight for wifi distance.

237 miles is the distance record, but you need to be on the peaks of an Andes mountain range, heh.

http://www.engadget.com/2007/06/19/venezuelans-set-new-wifi-distance-record-237-miles/

How would you attach a wifi antenna to your laptop/desktop?

Some wireless routers have an external antenna connector.

One way is to use a wireless network card that has a detachable SMA type small whip antenna. Then use low loss 50 ohm cable with the proper SMA connectors. Thats what I used on my wifi biquad. The low loss cable still has a lot of loss, so youre limited to about 10 ft max cable distance, without some kind of repeater.

Another option is to use a weatherproofed usb b/g adapter for the antenna element and a usb extention cable.

Yep, don't go using 75Ω coax, it has to be 50Ω.

I needed some 50Ω coax in a hurry once to fix a 2-way radio so I stopped into a big box store's automotive department, bought a replacement AM/FM car antenna, sheared off the Motorola connector, cut the remaining 3 feet of cable off the antenna and soldered the right connectors on, all for about $7. Worked perfectly. :) Some stores have an extension cable for car antennas which would do even better.

Cool, I actually have an MN-730 I'm not using that has a detachable whip antenna (just unscrewed it!), and, a couple USB b/g adapters too.

What would the approx limit be using a USB extender cable on with the USB wireless thingys?

EDIT: No antenna jack on the router - I gues that just would have made too much sense.

Q1: How long of a cable can I use to connect my device?
A1: In practice, the USB specification limits the length of a cable between full speed devices to 5 meters (a little under 16 feet 5 inches). For a low speed device the limit is 3 meters (9 feet 10 inches).
http://www.usb.org/about/faq/ans5

So, with 15 feet to a powered hub, and another 15 feet to the usb b/g adapter, about 30 feet.

I just built a mini-reflector for my router out of tin foil :)

Will see if it improves the situation in my bedroom any. I mean the reception of course ;)

It helps a lot!! I'm going to make a better one, more shaped to my situation.