Originally Posted by srnet
Start with a bit of wire about 1 wavelength long, 12.5cm for 2.4Ghz and cut little bits off in stages to see if range is affected.
The classic length for a single wire would be 1/4 wavelength (3.2cm) but as mentioned previously you may well find that this is not the length for maximum output and thus range.
Will give a try
One more thing...wire sideways or pointed straight up? Or perhaps the more correct question is...Try to keep the antenna pointed at the rx or perpendicular to it?