Newsgroups: comp.robotics
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From: sarge@Rational.COM (Matthew C. Sargent)
Subject: Re: RF communication
Message-ID: <1993Sep14.195332.5080@rational.com>
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References: <274qfu$kkv@osceola.cs.ucf.edu>
Date: Tue, 14 Sep 1993 19:53:32 GMT
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Eric Wampner (wampner@acme.ucf.edu) wrote:
: Long posting, 

: In article <1993Sep13.124224.27564@amoco.com> zjoc01@hou.amoco.com writes:
: >I have seen in the back of popular electronics mag's, spy type of RF 
: >transmitters.  I was wondering if someone could help us come up with
: >a cheap modem and reciever for use with these?  This could answer your
: >question...

: After looking through a Nuts and Volts, and 4 or 5 data books, I have
: learned a bit more. Conviently Nuts and Volts has a project which does
: transmission of data (Solar Exporer, Sep 1993), but they use two "bad"
: things, morse code, and two meter band ham radio. Morse code I might be
: able to deal with, since I can just replace it with something more simple,
: but I am not going to put a 2m ham radio in every device I use to 
: communicate with. Plus they talk about tuning it, and my eyes glaze over,
: yeah, spectrum analyzer, got one of those right here, right.
The guy who wrote that article for Nuts & Volts (Nick Goss) is a very
nice guy. I have called him many times to ask about modifications
to his circuits for my needs. He has a large number of simple and
effective circuits that might help you out. He also has a 
manual of all his curcuits etc. that teaches you alot about
the circuits and parts of them. If you look in the ordering information
for the Solar Explorer you will seee the phone number and address. You might
want to contact him and ask directly.

Since you are using a fairly limited range, you may want to go infrared,
it is easy and lots of single chip solutions exist. You might also
want to consult Caircia's Magazine Circuit Cellar (I think) I remember
a whole series dealing with X10, Infrared person locators and information
beacons...


: The FM stuff sounds like it might be okay, but todays one chip modems
: have outputs which are designed to connect to the phone line, not an
: audio in/out, any hints?

: I have seen some good circuits in a Signetics catalog, I couldn't copy
: it so i don't have the specs, but they have some FM transceiver circuits,
: plus a really cool chip, the NE5050 Power Line Modem, which does everything
: you need to do something like X-10 over the power lines in the houes.
: Not cool for robots, but fairly cool for home apps.

: The problem about the FM stuff is that they are fairly vaque about the
: circuit, I will have to get a copy and read it a couple of times before
: I will know if it will do what I want.

: So, who would I talk to about some more obscure chips in low quantity
: orders? Call the main company? Ask for some free samples?

: Whats the power limit on transmissions before the FCC gets concerned?
: I think the band was about 100Mhz.

: <what this is all about>
: >
: >In article 9qk@osceola.cs.ucf.edu, wampner@longwood.cs.ucf.edu (Eric Wampner) writes:
: >>>
: >>>I am looking for RF based communication circuits, specifically
: >>>ones which will allow communication around a typical house.
: >>>

--
=============================================================
| Matthew C. Sargent         |  My opinions are my own. Any |
| sarge@rational.com         |  similarity between them and |
|                            |  other opinions, living or   |
|                            |  dead, is accidental.        |
=============================================================
