Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!ukma!rex!ames!vsi1!daver!wombat!george
From: george@wombat.UUCP (George Scolaro)
Newsgroups: comp.sys.handhelds
Subject: Re: Easy HP infra-red PC receiver.
Message-ID: <1231@wombat.UUCP>
Date: 16 Jan 90 06:42:16 GMT
References: <5916@sdcc6.ucsd.edu> <10169@microsoft.UUCP> <843@wombat.UUCP> <692@kunivv1.sci.kun.nl>
Reply-To: george@wombat.UUCP (George Scolaro)
Organization: Assn. for the prevention of Polar Bears and Kangaroos
Lines: 24

In article <692@kunivv1.sci.kun.nl> ge@kunivv1.sci.kun.nl (Ge' Weijers) writes:
>george@wombat.UUCP (George Scolaro) writes:
>A bit more information on this would be welcome. The circuit sounds simple.
>The problem with the Radio Shack thing seems to be the automatic gain control.
>Not a problem with a TV remote control, but a pain with a calculator.
>What IR receiver did you use? (If it's a minidip receiver, what's the MC3373
>for? I haven't used one of those)

The MC3373 is an IR receiver, and is in an 8 pin minidip. All it takes is
three IN914 diodes a few caps a few resistors and an npn transistor + IR
photodiode to make it all work. The IR photodiode was bought at a surplus
place (I just bought one of each and chose the one that worked best). The
receiver works with the calculator up to a metre or two away, beyond that
it is very flakey (I assume because the printer outputs a fairly low level
output to conserve the batteries). The setup seems insensitive to external
lighting, either fluorescent or reflected outdoor light (sol). The major
drawback is that it runs on +12v.

regards,

-- 
George Scolaro
george@wombat
(try {pyramid|sun|vsi1|killer} !daver!wombat!george) [37 20 51 N / 122 03 07 W]