A quick search on Ebay shows some IRDA add-ons, mostly USB, some
serial.  Heres one($20.00):
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2041232359
You probably can't buy the parts for much less than this.

Not sure if it has support under Linux, a few quick Googles showed
some linux references.

Most laptop/motherboard IRDA ports are preconfigured to just work,
while the dongles require special initialization codes sent to them
and proper RS232 handshake signals set to power them.

Any serial-port dongle will just be SIR(slow infrared, up to 115200 bps).
IRDA FIR is a different mode, typically at 4M bps,
supported by some USB and built in IR ports.  Google on "ronja"
for a open 10Mbps 100 meter IRDA project that should keep you
busy for the rest of the year :)

I mentioned selling some home-made serial IR dongles previously,
but I'm afraid I confused some people, the gadgets I make
are for TV remote control, not for IRDA data transfers.  They
allow you to control your PC with a remote control or control
your TV/VCR/stereo with your PC.  The two use slightly different
physical layers.  You can sometimes do limited range TV remote
control with IRDA SIR ports.  See http://www.lirc.org, or my
ugly web page at http://www.turbobit.com/lirc.html for more on
TV remote control.

I'm working on using a PC as a jukebox and a remote control
as an interface to it.  This sort of thing is gaining popularity
with the new PC killer app "tv/video/recording..".  And of coarse
the 80G/$80 drives help :)
Many of the new TV-tuner cards come with a remote control.
Right now I have a cheap Win-TV tuner card($30-$40) that works good,
I can record TV shows, do full screen TV, record from VCR tapes.
I can't do TV out yet, keeping my eyes open for an inexpensive
solution here.

Maybe this sort of thing would make a good monthly meeting
topic: multimedia stuff under Linux(linux is not just
for networking geeks anymore!).

Karl.

On Wed, Jul 24, 2002 at 02:33:39PM -0500, Austad, Jay wrote:
> Does anyone have a link to a page with plans on how to build one of these?
> I was going to buy one, but they cost a minimum of $50, plus, I need
> something to build because I'm getting ansy and I might have to modify the
> potato cannon if I don't find something else to keep me busy.
> 
> Jay
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