Thinkpads Forum

I've tried looking online to see what the actual output power (mW) of this card is, and I can't find any answers. I'm assuming the antennas are standard "zero gain" antennas, and that while the adapter can use multiple antennas--there's no clean way to add an external here?

I'd like to find out the output power of the card to get a fast idea of whether it is worth using an external card/radio and gain antenna in some areas where WiFi is weak.

Anyone?

sailor,

Interesting question.

If you double click on the bottom right access connections icon, it will say 25mw transmit power.

I wonder if there is any additional control on the transmit power?

On the antenna, IMO because the 4965 antenna is fairly large and in the lid of the PC, I believe it will be higher gain than any typical pcmcia or usb antenna gain (>1-2db) but I don't know the exact number. My guess is that the antenna is omnidirectional as well.

Since the antenna line coming out of the 4965 is 50 ohm, you could actually connect a high gain antenna but it would require some eng effort to be sure the connection is correct and you don't end up losing gain instead of increasing gain.

But, I would be interested to know the exact answer to the first two questions. In the end, with six pcmcia and usb dongle wireless cards, i can compare signal strengths but the answer is more qualitative than exact.

Apologizing for the long answer.......

Alacrity-
AFAIK, all Wifi equipment is designed to negotiate power levels and the 25mW output just means your computer is close enough to your router so it can operate at low power. I doubt there's a card on the market that has less than 100mW output power, and 200mW is not unusual. (400mW is [censored] hard to find.)
I'm familiar with cabling, impedance matching, and the radio tech sides of things, that's no problem for me. Finding good quality low-loss cable, also no problem.
Most of the laptops I've seen specs on put the antenna in the display's border, so it gets an unobstructed "view". These are nice in that they normally have two antennas installed, and the Intel radio has the ability to actually use THREE antennas at once in what is called "diversity" mode, where it polls all three and uses the one with the strongest signal. Since one of the built-in antennas is horizontal and the other is vertical, our setup starts out very nicely because you can lose a great deal of performance if your antenna is not oriented the same way as the one at the other end. Typically, 10-20dB of signal loss that way, which is more than a 90% difference in signal strength before you even start.

FWIW, the land distance record for "unboosted" WiFi is over 150 miles right now--but those folks did use a 12-foot dish and some special software (to override latency aka time delay limits) to make that happen. I'm not that ambitious, I just want to push it further than I can throw a baseball.<G>

sailor,

Please keep posting so we can follow your progress or results.

I see on another forum:

"the iwl4965 driver has neither the non-standard Intel iwpriv interfaces, nor the standard iwconfig interfaces for enabling any kind of powersaving features, including changing the transmit power of the card"

This was in Linux on the Lenovo but i wonder about the 4965 power and the ability to adjust it either way. And, yes, 25mw seems low but i would like to see more spec info out there to confirm higher power levels.

Also, in advanced access mode, it shows the 4965 at 100% of transmit power for the 25.1mw.