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From: bender@oobleck.Eng.Sun.COM (I want to be eating rich soup in another town)
Newsgroups: sci.electronics
Subject: Re: CHEAP WIRELESS MODEM IDEAS?
Message-ID: <10673@exodus.Eng.Sun.COM>
Date: 28 Mar 91 22:37:20 GMT
References: <426@mixcom.COM>
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Distribution: usa
Organization: Sun Microsystems, Mt. View, Ca.
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In article <426@mixcom.COM> jjwwjj@mixcom.COM (Robotic Systems) writes:
->Does anyone have any suggestions for a way to implement a cheap, simple (under
->10 chips) wireless modem? I need atleast 300 bps and a 25 meter range.

Would this work?  Since the FM (stereo) transmitter has two audio channels
with probably at least 15kHz bandwidth, could you use two transmitters and
two receivers as a two-channel bidirectional data communications link?  Or
even if there's too much crosstalk and not enough channel seperation between
the two channels, how about just two FM transmitters and two FM receivers?
And of course the requisite circuitry to modulate/demodulate the data
stream onto the audio channel.  Maybe pick up two cheap 2400 baud modems
and split the signals out from before the phone line hybrid??

mike
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