Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Adding a 38kHz carrier to IR
Adding a 38kHz carrier to IR
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 6th July 2006, 12:28 AM   #1
rtarbell is offline rtarbell  United States
diyAudio Member
 
Join Date: Sep 2005
Default Adding a 38kHz carrier to IR

For an infrared remote controller, does someone have a quick and dirty circuit to add a 38kHz carrier to a digital signal (such that a digital "1" transmits the carrier, and a digital "0" transmits nothing)?
  Reply With Quote
Old 6th July 2006, 03:10 AM   #2
banana is offline banana  Hong Kong
diyAudio Member
 
Join Date: Feb 2003
Location: Hong Kong
D flip-flop
  Reply With Quote
Old 6th July 2006, 10:38 AM   #3
seoman is offline seoman  Netherlands
diyAudio Member
 
Join Date: Apr 2004
Location: Nijmegen
I think this would do the trick

Make sure that you either use a darlington transistor with normal diodes or a normal transistor with schottkey diodes.

Regards, simon
Attached Images
File Type: gif ir.gif (3.2 KB, 138 views)
  Reply With Quote
Old 6th July 2006, 04:45 PM   #4
rtarbell is offline rtarbell  United States
diyAudio Member
 
Join Date: Sep 2005
Thank you very much!
  Reply With Quote
Old 7th July 2006, 02:13 PM   #5
macboy is offline macboy  Canada
diyAudio Member
 
Join Date: Oct 2003
Location: Ottawa, Canada
That solution requries that the carrier be supplied separately, which is great if the carrier is already available. One trick to both generate the carrier and modulate it is to use a 555 timer, configured to output 38 kHz with 50% duty cycle, and use its reset pin to modulate the carrier with the digital signal. When reset is asserted, the 555 stops oscillating, and when it is deasserted, it starts again. The output of the 555 is sent to the IR leds, and since the 555 has high drive current you can usually drive them directly.
  Reply With Quote
Old 7th July 2006, 10:14 PM   #6
gmarsh is offline gmarsh  Canada
diyAudio Member
 
gmarsh's Avatar
 
Join Date: Apr 2004
Location: Halifax, NS
Quote:
Originally posted by macboy
That solution requries that the carrier be supplied separately, which is great if the carrier is already available. One trick to both generate the carrier and modulate it is to use a 555 timer, configured to output 38 kHz with 50% duty cycle, and use its reset pin to modulate the carrier with the digital signal. When reset is asserted, the 555 stops oscillating, and when it is deasserted, it starts again. The output of the 555 is sent to the IR leds, and since the 555 has high drive current you can usually drive them directly.
What he said; I've done exactly this trick in the past.

Though in a 3.3V or 5V land, use a TLC555 timer instead of a NE555.
  Reply With Quote

Reply


Adding a 38kHz carrier to IRHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
fullbridge carrier class d ideas Tekko Class D 12 25th March 2011 09:00 PM
people carrier sounds NED 209 Car Audio 3 31st December 2008 01:11 AM
Tube sockets without the ceramic carrier. ashok Tubes / Valves 5 16th May 2007 08:24 AM
Carrier Current AM Radio transmission akersa Parts 2 13th April 2003 04:57 PM


New To Site? Need Help?

All times are GMT. The time now is 12:46 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki