Sign in to follow this  
hamoodyjamal

Infrared Activated Switch

Recommended Posts

Hi Audioguru,
now i have done my project with lm567 but it didn't work as i want. I use a LED as a load. But the LED still "ON" no matter the input frequency is out from my bandwidth setting. I've try a couple solution (like add a low pass filter) but it didn't change. I use a lm567 as a tone decoder from the frequency that i was send from FM transmitter (i was use ne555 as the information frequency). Can you give me any solution with this problem? thanks, and i hope your reply as soon as.

Share this post


Link to post
Share on other sites

Hi Indra,
Welcome to our forum. ;D
Philips recommend a 0.01uF to 0.1uF ceramic disc capacitor directly across the power supply pins of their NE567 and an additional 10uF electrolytic cap if the supply has poor voltage regulation like from a battery. They also say to be careful with signal routing and to avoid ground loops.

Try disconnecting the input capacitor of the 567 from its driving stage and connecting the capacitor to ground instead to see if the LED turns off. If it does, then the problem is with the driving stage. ;D

Share this post


Link to post
Share on other sites

Im baaaack!

Wow, that took longet than i expected. Was fun though.

I see someone has built this project, or part of it. and is having some trouble. I couldn't quite understand what he/she wrote. Maybe you can shed some light on it?

I presume the cuircuit i should build works fine???? you know, the one with the TL072 and NE567.

;D

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this