[sci.electronics] FM Transmitter/Reciever for Data

reid@hplvec.LVLD.HP.COM (Reid Trimble) (03/28/91)

I think this might be what you had in mind:

From kellym@ether.UUCP Tue Mar 19 10:38:35 1991
Relay-Version: version Notes 2.8.4  1990/05/09; site hplvec.LVLD.HP.COM
From: kellym@ether.UUCP (Kelly M McArthur)
Date: Tue, 19 Mar 1991 17:38:35 GMT
Date-Received: Fri, 22 Mar 1991 02:06:54 GMT
Subject: Re: FM transmitter/receiver chips
Message-ID: <1727@ether.UUCP>
Organization: HALF, Beaverton, OR
Path: hplvec!hpfcso!hplabs!ucbvax!ucsd!swrinde!zaphod.mps.ohio-state.edu!mips!cs.uoregon.edu!ns.uoregon.edu!milton!uw-beaver!zephyr.ens.tek.com!tektronix!sequent!ether!kellym
Newsgroups: sci.electronics
References: <1991Mar14.025500.11882@s1.msi.umn.edu>
Reply-To: kellym@ether.UUCP (Kelly M McArthur)
Keywords: transmitter, receiver, FM, I.C.
Lines: 25

In article ... tomv@s1.msi.umn.edu (Tom Varghese) writes:
>
>I am looking for an simple, cheap FM transmitter/receiver circuits to use
>as a medium for digital data transmision over a short range (~100 yards)....
>I was wondering if there are any single chip solutions for this.

Motorola's MC2833 might be useful to you.  It is a single-chip FM transmitter
with an audio input you could use for FSK, and a built-in 
microphone preamp you can loop back into the audio input.  In addition, 
if you call the Motorola folks in Phoenix, they'll cheerfully send you a
little evaluation PCB you build up a test circuit on (or at least they did
for me). The part is found in the "Linear and Interface Integrated Circuits"
book.  

The data book lists values of caps and coils to operate this
device at 49.7 MHz, 76 MHz and 144.6 MHz  (note that values for operation
at ~100 MHz are conspicuously absent :~)  ).  Power output is listed as
+5 or +10 db. (BTW, how do you relate this to something like milliwatts,
for those of us who don't speak RF-ese?).

					Have Fun,
-- 
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