On 27 Jul 2009 02:12:14 +0200, alfredeneuman
<alfredeneuman@whatmeworry.org> wrote:
>Jeff (or others if they know) can you take a look at these test reports
>and give me a better idea of which of these units will most likely
>bring in the most stable; best signal on a 802.11b old desktop?
No, I can't. All the FCC reports will show is TX power output and
occupied bandwidth. There's nothing on RX sensitivity, dynamic range,
BER/PER tests, and interference/reflection rejection. They do show
the chipsets used, which will probably give the most useful info:
>Have
>already checked OS support for these radios, but I don't have the
>expertise/knowledge to evaluate the test reports. I will be using a home
>brew parabolic reflector behind the antenna to maximize signal strength.
Yep. A better antenna will always improve range and reduce junk
pickup from the sides and back.
>Getting fair to good now with a good pcmcia card, but want to go to a
>desktop that has not ethernet or pcmicia support, hence usb.
Make sure it's USB 2.0. You didn't bother supplying the operating
system, but my guess is that if you insist on 802.11b, it might be
ancient.
>Let me know
>if I have left anything out.
Equipment used.
Access point or wireless router used.
Why only 802.11b?
Operating System and revision level.
Estimated range?
Line of sight?
Makers and model numbers of radioA thru C.
>Also, for future reference aka evaluation
>for dummies, which stats in the test report are the best indication of
>quality of the radio?
Not much. There's also no single number or graph that defines
quality. It's also possible to take a perfectly good chipset, and
ruin the performance with a buggy driver. This is all to common with
USB, which is why I prefer ethernet. If pressed, I tend to look at
the graph of RX sensitivity versus speed at a fixed BER or PER. That's
not on the FCC reports.
>http://tinyurl.com/mddlvy radioA
ARGtek ARG-U25G
802.11b=19.2dBm 802.11g=18.3dBm (about 80mw)
Huge heat sink which makes me wonder if it get hot.
RTL8187B and SiGe 2527L chips.
I'm not happy with Realtek drivers and am unfamiliar with the 2527L
chip.
>http://tinyurl.com/lox776 radioB
TP-Link TL-WN422G
Atheros AR2524-AQ1C chip. I can't identify the RF chip.
General layout looks nice. I like the PCB RF bandpass filter near the
antenna connector, but it might be lossy. Dunno.
20.8dBm max power output (about 100mw)
>http://tinyurl.com/mr9d3r radioC
Rosewill RNX-G1 or RNX-G1W
TX power 12-13dBm. (about 11 to 20mw). See 8.4 of test report.
Realtek RTL8187B. I can't read the RF chip, but it's another Realtek,
possibly an RTL8255.
I have the same problems with Realtek on this unit.
This is a no brainer. The 2nd one (TL-WN422G) has the best chipset,
the best layout, and highest Pout. (Incidentally, this took 45 mins).
--
Jeff Liebermann
jeffl@cruzio.com
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Hey Jeff, can you look at these for me? 
Linear Mode
