Wireless

[anuradha]

hi
this looks funny but I'm trying to create a wireless chat room
Basically I'm trying to connect two computers wirlessly.I'm not talking about WI-FI or any other method.
i'm hoping to use a simple transmitter and receiver.Also I will use USB port to connect the transmitter and receiver.
Is it possiable to do this kind of thing. any suggestions on this??? :dazzled: :dazzled: :dazzled:
thanks

[u]

What makes you think it's not possible :).  The key term here is not "wireless", but "radio" - this will return more good search-results in google, as back in the days we all called it radio, then came the terms wireless phones, (then gsm) and then wifi+bluetooth (which is what people use mean when they say "wireless" now).
Radio is both amazingly simple and hard (to tune the resonant filters and RF amplifiers).

You start-off with wanting it to be USB, which makes the project a hell to handle at start-up.
Start-off by making a button-controlled AM transmitter and a receiver that lights-up a LED when that button is pressed, and work from 5V supply.

[anuradha]

hi
first thanks for the reply.
I know this is too much.but i have a software that can send txt messages using com ports.but two mechines have to be connected
using a cable. so i thought instead  of cables why not radio signals.

Code Select Expand

What makes you think it's not possible

because I'm new to electronics.I have studied as a subject in my physical science degree course.
but its not much.so thats why I asked for help.so
any good tut on RF??

[u]

Dunno about tutes online, I've learnt everything I know about RF from dozens of big old Russian books (plus datasheet books), plus some even bigger books written in my language ^^". And lots of experimenting, though making my own PCBs and tuning the schematics was always a problem for me - I'd always get one right, but fail at the other  :green2.
(you can get away without a PCB, and with using chunks of published simple schematics that are known to work).
Keywords: RF AM transmitter, AM demodulator, common-emitter

[zooba]

You're probably best off looking for kits. You can get pre-built single-bit transmitter and receiver kits that mean you don't have to worry about a lot of the technical difficulties behind RF transmission and reception (and trust me, it's not trivial :bg ).

Also, you'll find using a serial or parallel port much simpler than USB - search this forum for some of the other USB posts to see what I mean. There's a lot of work that can be avoided for very simple applications. (If you don't have a serial port, get a USB to serial adapter. It will be cheaper than the equipment needed for USB development.)

Cheers,

Zooba :U