Newsgroups: comp.robotics
Subject: Re: REQUEST: Simple Sing
From: henry.liu@tabb.com (Henry Liu)
Path: brunix!cat.cis.Brown.EDU!agate!library.ucla.edu!psgrain!nntp.cs.ubc.ca!torn!uunet.ca!uunet.ca!tabb!henry.liu
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Message-ID: <66.960.1262.0N5C599C@tabb.com>
Date: Sat, 16 Jul 94 15:32:00 -0500
Organization: Timmins Area BBS (705)268-0801
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In a message on 07-07-94 12:17 Darryl Palmer to ALL about  "Re: REQUEST: 
Simple Sing" 
 
DP>DP>DP>Message-ID: <1994Jul7.171732.13497@news.csuohio.edu>
DP>Newsgroups: comp.robotics
DP>Organization: Cleveland State University


DP>Wally Blackburn (wrb@ccsitn.cb.att.com) wrote:
DP>: Since we're on the subject of wireless data links:

DP>: I've been toying with the idea of a wireless data link along the line
DP>: the one in Jan Axelson's MicroComputer Journal article.  She used a p
DP>: Ramsey FM-10 transmitters and cheap FM radios with some AM7910 modem 
DP>: Anyway, I've been looking at that and other possibilities and I came 
DP>: the Holtek tx/rx boards in the Digi-Key catalog.

DP>: They have a 310 MHz serial data input AM SAW transmitter for $17.16 a
DP>: companion receiver for $20.30.  So I said "Bloody hell, why am I mess
DP>: around trying to build a 1200 baud link for $100 when I can buy these
DP>: things for about $40?!"

DP>: Has anybody used them?  What is the max data rate?  What is range lik

DP>: PS.  They also have an FM pair for TX: $50.09, RX: $62.64.  Any exper
DP>:      with these?

DP>: -- 
DP>:    Wally Blackburn     Clinton-Gore - Socialist Leadership
DP>:    wrb@ccsitn.cb.att.com            for the 90s!
DP>:    Amateur Radio Station AA8DX    I'm the NRA.
DP>:    '91 FXR DoD #1375

DP>I used these kits (Actually the kits are not made by Holtek, they are m
DP>Ming but they use Holtek chips) for an e-stop for the AUVS ground compe
DP>When we measured out the distance it was around 120+ ft.  As far as dat
DP>I haven't tested it but I remember reading that the "code" signal has t
DP>be valid for a little while, like 1/2 seconds, before it would latch th
DP>data pins for you.  There are 4 bits of data if you use an 8 bit code w
DP>a relay already built in for driving things (We used it with a relay) o
DP>you can use the other chip they provide to get a 12 bit code and a rela
DP>output.  If you think you are going to get it, I will check on the supp
DP>we went with. They offered the TX, RX, and also keychain TX for only 40
DP>bucks.  The keychain only allows you to transmit 1 or 2 bits, but it is
DP>really small.

DP>The 120 ft we got with the kits were with the antennae they provided (O
DP>internal PCB trace for the transmitter and I think a 1/4 wave for the
DP>receiver), but if you go with a full wave or a real TX antenna you coul
DP>increase the distance.  If you are going to use this, I have to repeat
DP>what the docs said, THIS UNIT IS FOR EXPERIMENTAL PURPOSES AND IS NOT F
DP>TESTED.  Like it made a difference to me.

I'm very interested in this.  I'd like to be able to transmit 2 anlogue and 
2 digital lines.  Do you think it could do this?  If not do you know of 
anything/anyways to do this.  Your help will be greatly appreciated.
ttyl
Henry

DP>Darryl Palmer
DP>Grand Poobah and President
DP>IEEE Student Chapter
DP>Cleveland State University






Henry Liu (henry.liu@tabb.com)
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 * WaveRdr 1.10 [NR] * UNREGISTERED EVALUATION COPY
