[plug] Wireless LAN questions (time for a Milo break)

[bob]

On Sun, 13 Jan 2002 10:55, Leon Brooks wrote:
> Customer is unusual in that he's prepared to wield a (+1 damage) soldering
> iron.

In that case they'd be interested in this...

http://atrey.karlin.mff.cuni.cz/~clock/twibright/ronja/

Ronja is an Open-Hardware optical datalink that connects two PC's 
point-to-point. Ronja's design is licensed under the GNU Public License: you 
get all the necessary documentation and construction guides free. The 
construction costs are minimal; it's probably the cheapest wireless system 
ever. The operation is very reliable and immune to interference.


Ronja 10M Metropolis Technical Specification

    * Bit rate and transmission mode: 10Mbit, full duplex
    * Maximum operating distance: 1km wih 130mm lenses, 500m with 90mm lenses.
    * Minimum operating distance: 1/15 of maximum operating distance. Further 
manual reduction possible by change of two passive components.
    * Data interface: IEEE 802.3 Attachment Unit Interface (AUI) except 
mechanical latch requirement
    * Power consumption: 300mA @12V (3.6W) from AUI, 2W from external heating 
power supply (switchable off)
    * Operating wavelength: visible, 625nm, 100nm spectral width (618nm 
perceived wavelength, red-orange)
    * Estimated optical output: 12mW
    * Divergence cone half angle: 1.9mrad (130mm aperture transmitter lens)
    * Estimated Optical EIRP: 10kW (130mm aperture transmitter lens)
    * Operating humidity: up to 100% with lens heating on, up to 95% with 
lens heating off. Certain atmospheric visibility required.
    * Optical modulation: BPSK (as on AUI) plus 1MHz asynchronous 50% duty 
cycle square wave between packets.
    * Indicators: Power, Receive Packet, Transmit Packet
    * Aiming system: visual, retroreflector for transmitter and DC voltage 
signal strength monitor port for receiver.

Mmmmm ... Open source hardware.  :)

-- 
"Mr. Watson, come here, I want you."   -- Alexander Graham Bell