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From: wrb@ccsitn.cb.att.com (Wally Blackburn)
Subject: Re: REQUEST: Simple Single Channel 27MHz TX/RX circuit diagram
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References: <2veb0m$k5m@unixfe.rl.ac.uk> <quartlowCsK3v3.MJs@netcom.com>
Date: Thu, 7 Jul 1994 12:55:31 GMT
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In article <quartlowCsK3v3.MJs@netcom.com>,
Len Turnbow <quartlow@netcom.com> wrote:
>Rafe Aldridge (rca@sirius.tn.rl.ac.uk) wrote:
>: Hello all,
>
>: Does anyone have a circuit diagram for a simple single channel
>: 27MHz Transmitter and reciever?
>(Snip)
>
>How about a pair of kids walkie-talkies?  You could tape down the 
>transmit switch on one, viola! That's your transmitter.
>At 100mW to the final, two meters range might be difficult. ;^)
>More expensive walkie-talkies have switching circuitry built-in
>that would allow you to establish a half-duplex link via relay control.
>
>Hope this is helpful.
>
>--quartlow

Since we're on the subject of wireless data links:

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

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

Has anybody used them?  What is the max data rate?  What is range like?

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

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