hi, got a second PC in another room and want to be able to connect the
second one to my wireless router to access the internet. is it best to
install a wireless card in the second pc,or can i use a usb dongle(not
sure what this is) to do this. XP on first pc, ubuntu 9.4 on the
other. thanx for any help/ advice Don
Some potential advantages of a PCI Wifi card.
1) Room for them to use a separate radio chip. The radio
chip may have better performance (they could use CMOS for
the MAC, and bipolar transistor technology of some sort
for the radio chip - allowing the best technology for each
portion).
2) PCI cards may have an external connector offered, allowing
the antenna to be connected there. A short whip antenna may
be provided, but you can also connect a length of cable and
antenna if you want.
This PCI card, uses a Ralinktech chipset. The MAC chip is outside
the shield area (it doesn't deal with radio signals). Other chip(s)
are hiding underneath the metal RF shield.
http://c1.neweggimages.com/NeweggImage/productimage/33-315-041-09.jpg
The standard antenna connector on the faceplate, means you can substitute
other antenna solutions if you want.
"External detachable dipole antenna (Connector: RP-SMA connector, Cable Length: 94 cm)"
http://c1.neweggimages.com/NeweggImage/productimage/33-315-041-12.jpg
Some come with a whip that bolts to the faceplate, so you don't have
cables dangling. But you cannot easily move this, to experiment with
reception. As long as the antenna is actually connectorized and not
permanently affixed, you can remove it and substitute something else.
So with some products, it is easier to verify that the connector
is removable. Or it may be stated as such in the advert. If you
saw "RP-SMA" for example, that implies a removable connector.
http://c1.neweggimages.com/NeweggImage/productimage/33-180-030-01.jpg
*******
USB dongles vary greatly, even unit to unit of the same model
number. Some models of dongle are uniformly bad, while others
you can find strong ones and weak ones.
You can use the customer reviews on Newegg, as a metric for
what kind of product you're looking at. If you have brand and
model number information, you can try looking up the product,
and see what people think about it.
A USB dongle may use an antenna structure, drawn in copper on
the PCB of the dongle. That is where the antenna is hiding.
I have no idea, how effective these are, compared to the
external whip style. My suspicion is, that variable performance
could be as much a function of shady silicon, as an actual
antenna malfunction.
To see an example, you can download documents from the companies
that make the chips. For example, this one has a MAC chip that
sits outside the shield. The radio chip sits underneath the
shield area. The antennas are on the right. The "squiggle"
just before the antenna, is an example of the "magic of microwaves".
Microwave designers design filter elements, using nothing but the
shapes of copper on the PCB. The squiggle for example, could be
a filter to exclude unwanted RF energy (not part of what
they want to broadcast or receive). Having worked with a
guy who does stuff like that, it is a curious science,
and their designs are interesting, just for the
shapes used. Virtually everything in a design is a
"what does that do?" kind of question
http://www.atheros.com/pt/bulletins/AR5008-2NGBulletin.pdf
Paul
