<snip> 
> roddog wrote:
> 
> > O.K. So you want a bad as* card for wardriving?  
> > What you need is a Senao/Engenious? card with 2 antenna ports on it.
> > These cards have a better sensitivity than just about anything out there
> > next to Demark
> > and they also have 200mW of power which is the most powerful out there.  
>

Brian Lloyd writes next:

> A couple of comments about the Senao:
> 
> As for sensitivity, the Senao card has better *published* receive sensitivity specs. 
>  It seems pretty good but I am not sure it beats the Cisco for RX sensitivity.
> 
> TX power does indeed seem to be about +23 dbm.
> 
<Brian's notes on antenna connection info deleted below here>

I agree with Brian - I've now had a chance to get a couple senao's on my 
bench, and while my 2 cards are _not_ a valid statistical sample size (which 
I clearly emphasized to the customer who handed them to me), I have noted
that both cards lacked the receive performance of the aironet/cisco 350
series cards.  They did both deliver the +23 dBm into 50 ohms (but most all 
of my cisco 350's exceed their +20 dBm spec by 1-2 dB).  given all this - the 
1-2 dB of extra xmit power compared to a typical cisco 350 weighed against the 
loss in receive (not enough samples to say definitively, but it's alot more
than the benefit of the transmitter) doesn't justify their use in MARGINAL 
links as a better alternative.  They still seem to be a great all-around card
for NORMAL links, and CAN be the best bang for the buck in many situations 
that don't call for the absolute best money can buy.  I hope they force cisco
to make a 200 mW "360" card!  It's the best part about market competition!

My hunch is that it was simpler and cheaper for senao to make a +23dBm card
with a so-so receiver than a +20dBm card with a great receiver - besides, 
marketing will LOVE being able to say "twice as much POWER" - when was the 
last time you heard a marketing hype "6 dB better code to noise ratio!"??

As a BIGGER note - (again - keep in mind 2 cards does not a statistical 
sample make) - placing them inside a calibrated RF anechoic + temp/humidity
chamber resulted in wider variance near the high end of their specified 
operating temperature (60c).  The performance in the unspecified area 
above 60c was substantially poorer than a comparable cisco card.  But why
is 60C so important?

Once again - if your card is kept at 22 deg C inside your house, you'll most
likely never notice - but if it's outside on a 100 deg F day - inside a box
on a pole in the sun and your link margin drops below zero - it's a big deal.
NOWDAYS, EVEN THE PCMCIA SLOTS IN LAPTOPS CAN GET TO 60C!  I just stuck a 
micro-thin type T T/C in between my 2 pcmcia cards on the laptop I'm using 
to write this - 23.2 C room temp, 56.8C in between the cards!  (and this is
a PII/350 not some 3.0G PIV rocket laptop that has a 90 watt adapter!)  Ever
pull out the card and notice it's hot to the touch?  Senao's spec sheet stops
at 60C for their high power card.  I'm just ~3C away from that temp on a 3 yr.
old laptop!  When my 2.0 Ghz laptop comes back from repair, I'll duplicate 
the "pcmcia slot temp" test on it. That thing is too hot for a "lap" sometimes.
I can't imagine how hot the pcmcia compartment is!

Cisco, on the other hand, rates their AIR-PCM35x series to +70C - AND THEY
MAINTAIN THER PERFORMANCE SPEC.  Through the whole temperature range and 
a little bit beyond.


I'm not getting these numbers out of thin air - read the spec sheets in person
http://www.cisco.com/en/US/products/hw/wireless/ps4555/products_data_sheet09186a0080088828.html

http://www.senao.com/service%20&%20support/Spec/NL-2511CD_PLUS_Spec.pdf

(funny - senao's older cards were only rated at 50C  -  then 55C, then 60C )

If it seems like this bugs me - it does to a degree - It's not fair for 
manufacturers to make impressive glossy ad slicks that have numbers 99.99%
of the population can never verify.  Too many people make buying decisions 
on bad data - then wonder why things don't work.  I've heard all too often
"but the box said it would go 5 miles!"  I guess it keeps customers comming
though...

Everett

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