even with a filter, sunlight contains plenty if IR (that's why you feel
heat when you go outside in sunlight (at least in summer :P))
 
try putting a cardboard tube (like from a roll of toilet paper)
around your IR detector so only your IR-led/laser's light
can get to it
 
                                          _____
>|-   ~~~>  ~~~>  ~~~> ()____[] <-ir detector
^- Ir led
 
Please feel free to flame me 'cause of my
poor ascii art diagrams (and 'cause I'm using
this porportionate font and the html'ness of
my reply :P)
 
     -James, N9XLC
     -jrhall@globalsite.net
     -certified NERD
-----Original Message-----
From: marco <marcoaurelio@PPA.COM.BR>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Monday, January 11, 1999 8:28 AM
Subject: Receiver IR w/ problems sunlight

Hi,
I'm using a PIC16C508A to transmit/receiver I.R. pulse (negative width pulse=5ms and positive width pulse=200ms).
The circuit board receiver IR no problems w/ absence light, but I've problems w/ sunlight and lamplight incandescent.
The receiver IR phototransistor w/ filter IR.
 
What's the problems ? Any suggestion ?. 
 
This is circuit attached.
 
Thank you.
 
Marco Aurelio B. M.
marcoaurelio@ppa.com.br