Some hardware questions

Hi,

I've spent the past few days reading around the topic of WiFi and would like to tap the experience of the forum now please.

I have a T42 Thinkpad with in-built Centrino/Intel WiFi that usually works well to pick up open source WiFI signals. However, occasionally it fails to see signals that the computers of my friends are seeing, and I'd like to remedy that. However, the questions that I've not been able to find answers to are:

1. Will buying a Proxim Orinoco Gold or a Senao 362 PCMCIA card lead to a better signal sensitivity than my in-built mini PCI card?

I haven't been able to figure out a way to tell what the sensitivity in mW of my in-built card is. They specs on the Proxim and Senao are for a sensitivity of 200mW but I've read that they really are more like 100mW.

Does anyone know what the sensitivity of a mini-PCI card in a Thinkpad T42 is?

2.Will buying an omni antenna with a 9dB gain and an SMA card lead to a better signal than my in-built antenna?

The context for this question is that I've read that because all 802.11g signals have a wavelenth of 12.5 cm this means that the ideal antenna is 6.25 cm, which is apparently what is inside the screen of my laptop. Furthermore, I've read that apparently higher gain is not necessarily better because the beam is more focused meaning that it tends to multipath.

Thanks very much for the replies!

Jack
mudcadet@hotmail.com

Usually wireless cards/inbuilt wireless is 30mW unless otherwise specified. You'll definitely get a better result with a PCMCIA card and an external antenna, but it's not really practical to carry the antenna around everywhere.

I don't know a hell of a lot about antennas and wave lengths, but I'm pretty sure that the total length of the antenna doesn't matter too much, it more the spacing of the things inside.

A larger wifi antenna will have sections tuned the same (the same length) as a smaller one -- it will just have more sections. Basically, it's just several smaller antennas in series.