{"id":1748,"date":"2009-04-27T09:46:49","date_gmt":"2009-04-27T14:46:49","guid":{"rendered":"http:\/\/mightyohm.com\/blog\/?p=1748"},"modified":"2022-12-28T12:55:32","modified_gmt":"2022-12-28T20:55:32","slug":"diy-tivo-ir-blaster","status":"publish","type":"post","link":"https:\/\/mightyohm.com\/blog\/2009\/04\/diy-tivo-ir-blaster\/","title":{"rendered":"DIY TiVo IR Blaster"},"content":{"rendered":"<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"http:\/\/mightyohm.com\/files\/flickr\/3477836908_bc02a1a13c.jpg\" alt=\"DIY TiVo IR Blaster\" width=\"500\" height=\"375\" \/><\/p>\n<p>Recently I discovered that our local cable provider will soon be discontinuing analog cable service for most channels. \u00a0 Because of this they are <span style=\"text-decoration: line-through;\">forcing<\/span> encouraging customers to get new cable boxes and upgrade to <a href=\"http:\/\/en.wikipedia.org\/wiki\/Digital_cable\">digital cable<\/a>.<\/p>\n<p>I hate <a href=\"http:\/\/en.wikipedia.org\/wiki\/Cable_box_(electronics)\">cable boxes<\/a>.\u00a0 More than just another piece of equipment to find a place for near the television, cable boxes waste power, always seem to take forever to change channels, contribute to the ball of wires behind the entertainment center, and add another remote control to the coffee table.<\/p>\n<p>Most importantly, a cable box prevents our old Series 2 <a href=\"http:\/\/en.wikipedia.org\/wiki\/Tivo\">TiVo<\/a> from being able to change channels directly, since it now has to negotiate with the digital cable box to receive TV signals.<\/p>\n<p>TiVo provides a workaround for this &#8211; the infamous <a href=\"http:\/\/en.wikipedia.org\/wiki\/Infrared_blaster\">IR blaster<\/a>.<\/p>\n<p>I would love to meet the engineer who came up with the IR blaster.\u00a0 Instead of pushing for a universal protocol to electrically connect cable boxes to things that may want to control them, some engineer came up with the incredibly <span style=\"text-decoration: line-through;\">stupid<\/span> great idea to stick an IR LED in front of the IR receiver of the cable box and use it to simulate a handheld IR remote control.\u00a0 The cable box thinks that the user is punching away at the remote (with lightning speed) while in reality a microprocessor is generating the remote codes and sending them to the LED.\u00a0 It&#8217;s both ingenious, and at the same horrific in so many ways.\u00a0 It grates against my engineering sensibility.\u00a0 What manager approved this?<\/p>\n<p>Back to the TiVo.\u00a0 The IR blaster that came with our TiVo was lost long ago, in a time when no unnecessary electrical-optical-electrical sillyness was required for it to function.\u00a0 Rather than spend $3 on eBay and wait a week to get a replacement, I decided to make one out of spare parts in my junk bin:<\/p>\n<ul>\n<li>an infrared (IR) LED<\/li>\n<li>a 1k resistor (not sure if this is necessary, safety first)<\/li>\n<li>a 1\/8&#8243; mono headphone plug with a couple feet of cable attached<\/li>\n<li>some heatshrink tubing<\/li>\n<li>duct tape<\/li>\n<\/ul>\n<p>I don&#8217;t know if the resistor is required &#8211; the TiVo may already have an internal resistor.\u00a0 I used 1k, if I see any problems with the cable box getting an intermittent signal I&#8217;ll try lowering the resistor to 330 ohms.<\/p>\n<p>The tip of the 1\/8&#8243; mono plug is positive.\u00a0 I connected the tip wire to the side of the LED with the longer lead (the side <strong>opposite<\/strong> the flat side of the LED).<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"http:\/\/mightyohm.com\/files\/flickr\/3477024591_6558ce93b6.jpg\" alt=\"DIY TiVo IR Blaster\" width=\"500\" height=\"375\" \/><\/p>\n<p>I tested the circuit by applying 3-5V to the 1\/8&#8243; plug (tip is positive) and used my digital camera to check if the LED is working.\u00a0 <a href=\"http:\/\/www.dpreview.com\/reviews\/sonydscv1\/\">My camera<\/a> has a decent IR blocking filter so I had to use nightshot mode to see it:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"http:\/\/mightyohm.com\/files\/flickr\/3477833858_84a9495579.jpg\" alt=\"DIY TiVo IR Blaster\" width=\"500\" height=\"375\" \/><\/p>\n<p>Finally, I put heatshrink over the LED connections and the resistor to avoid short circuits:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"http:\/\/mightyohm.com\/files\/flickr\/3477833420_555767665d.jpg\" alt=\"DIY TiVo IR Blaster\" width=\"500\" height=\"375\" \/><\/p>\n<p>Back in the living room I plugged the DIY IR blaster into the jack marked &#8216;IR&#8217; on the back of my TiVo.\u00a0\u00a0 A strip of duct tape to secures the wires to the bottom of the cable box.\u00a0 I bent the LED up to point at the cable box&#8217;s IR receiver (the purple dot shown in the really bad photo below, sorry).<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"http:\/\/mightyohm.com\/files\/flickr\/3477837884_e99dd246e6.jpg\" alt=\"DIY TiVo IR Blaster\" width=\"500\" height=\"375\" \/><\/p>\n<p>All that was left was to configure the TiVo using the cable box setup guide.\u00a0 Within a few minutes I had my TiVo controlling the cable box.\u00a0 The DIY IR blaster works perfectly!<\/p>\n<p>Not bad for $0 in parts (all stuff from my junk bin) and a few minutes of soldering.<\/p>\n<p>Update November 2016: In the vast majority of applications, the series resistor is not required. The majority of IR blaster circuits built into A\/V equipment (and video game consoles such as the Xbox) include built-in current limiting circuitry that makes the resistor unnecessary.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Recently I discovered that our local cable provider will soon be discontinuing analog cable service for most channels. \u00a0 Because of this they are forcing encouraging customers to get new cable boxes and upgrade to digital cable. I hate cable boxes.\u00a0 More than just another piece of equipment to find a place for near the &hellip; <a href=\"https:\/\/mightyohm.com\/blog\/2009\/04\/diy-tivo-ir-blaster\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">DIY TiVo IR Blaster<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":true,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[5,443],"tags":[36,201,200],"class_list":["post-1748","post","type-post","status-publish","format-standard","hentry","category-electronics","category-projects-2","tag-diy","tag-infrared","tag-tivo"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pioCd-sc","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"jetpack-related-posts":[{"id":2476,"url":"https:\/\/mightyohm.com\/blog\/2009\/10\/guess-the-cable-length-to-win-stickers\/","url_meta":{"origin":1748,"position":0},"title":"Guess the cable length to win stickers!","author":"Jeff","date":"October 8, 2009","format":false,"excerpt":"Part 1: An HP 3312A function generator is connected to an Agilent DSO1014A oscilloscope via a length of coaxial cable.\u00a0 The function generator is set to generate a square wave of frequency 1MHz. Based on the screen capture below, what is the length of the coax cable? The first person\u2026","rel":"","context":"In &quot;Electronics&quot;","block_context":{"text":"Electronics","link":"https:\/\/mightyohm.com\/blog\/category\/electronics\/"},"img":{"alt_text":"Unterminated Cable","src":"https:\/\/i0.wp.com\/www.mightyohm.com\/blog\/wp-content\/uploads\/2009\/10\/10v_unterm.png?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":2675,"url":"https:\/\/mightyohm.com\/blog\/2009\/12\/2009-in-review\/","url_meta":{"origin":1748,"position":1},"title":"2009 in Review","author":"Jeff","date":"December 31, 2009","format":false,"excerpt":"Wow, 2010 came a lot quicker than I expected!\u00a0 With one day to spare, here's a brief look back at some of the highlights of 2009 here at mightyohm.com. DIY PID-Controlled Soldering Hotplate: I needed a hotplate for surface mount soldering, so I built one from scratch using a milled\u2026","rel":"","context":"In &quot;Electronics&quot;","block_context":{"text":"Electronics","link":"https:\/\/mightyohm.com\/blog\/category\/electronics\/"},"img":{"alt_text":"PID Controlled Hotplate","src":"https:\/\/i0.wp.com\/mightyohm.com\/files\/flickr\/3200389041_3d2f7a7e3b.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":4695,"url":"https:\/\/mightyohm.com\/blog\/2012\/02\/tutorial-geiger-counter-data-logging\/","url_meta":{"origin":1748,"position":2},"title":"Tutorial: Geiger Counter Data Logging","author":"Jeff","date":"February 10, 2012","format":false,"excerpt":"http:\/\/www.flickr.com\/photos\/mightyohm\/6849183393\/in\/photostream So, you want to log data with your Geiger Counter kit? Here's how to do it! You will need: A MightyOhm Geiger Counter Kit\u00a0- available on this site or from one of my distributors. A USB-Serial cable I recommend the FTDI TTL-232R-3V3, available from many electronics suppliers, such as\u00a0Adafruit\u2026","rel":"","context":"In &quot;Kits&quot;","block_context":{"text":"Kits","link":"https:\/\/mightyohm.com\/blog\/category\/kits\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/mightyohm.com\/blog\/wp-content\/uploads\/2012\/02\/realterm-500x319.png?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":1962,"url":"https:\/\/mightyohm.com\/blog\/2009\/06\/wifi-radio-cost-breakdown\/","url_meta":{"origin":1748,"position":3},"title":"Wifi Radio Cost Breakdown","author":"Jeff","date":"June 10, 2009","format":false,"excerpt":"Many people have asked me for a cost breakdown of my Wifi Radio project.\u00a0 Well, here it is! I added a link to possible sources for as many parts as I could.\u00a0 However, there were a few things I scrounged from local surplus electronics stores and couldn't easily find a\u2026","rel":"","context":"In &quot;Electronics&quot;","block_context":{"text":"Electronics","link":"https:\/\/mightyohm.com\/blog\/category\/electronics\/"},"img":{"alt_text":"","src":"http:\/\/www.ftjcfx.com\/image-3238164-10440897","width":350,"height":200},"classes":[]},{"id":480,"url":"https:\/\/mightyohm.com\/blog\/2008\/10\/building-a-wifi-radio-part-3-hacking-the-asus-wl-520gu\/","url_meta":{"origin":1748,"position":4},"title":"Building a Wifi Radio &#8211; Part 3, Hacking the Asus WL-520GU","author":"Jeff","date":"October 30, 2008","format":false,"excerpt":"This is the third part of an ongoing series about building a low cost, open source streaming internet radio.\u00a0 If you haven\u2019t already, check out part one and part two for some background about the project. Hacking the Asus WL-520GU Wireless Router: In the last part of this series, I\u2026","rel":"","context":"In &quot;Electronics&quot;","block_context":{"text":"Electronics","link":"https:\/\/mightyohm.com\/blog\/category\/electronics\/"},"img":{"alt_text":"","src":"http:\/\/www.awltovhc.com\/image-3238164-10440897","width":350,"height":200},"classes":[]},{"id":1010,"url":"https:\/\/mightyohm.com\/blog\/2009\/01\/diy-pid-controlled-soldering-hotplate\/","url_meta":{"origin":1748,"position":5},"title":"DIY PID Controlled Soldering Hotplate","author":"Jeff","date":"January 17, 2009","format":false,"excerpt":"In preparation for my Arduino-based AVR HV Programmer boards coming back, I decided to step up my home lab surface mount soldering capabilities. Step one was to find a cheap stereo zoom microscope on ebay, with 7-32X magnification, perfect for working on surface mount devices.\u00a0 One of my biggest frustrations\u2026","rel":"","context":"In &quot;Electronics&quot;","block_context":{"text":"Electronics","link":"https:\/\/mightyohm.com\/blog\/category\/electronics\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/mightyohm.com\/blog\/wp-content\/uploads\/2009\/01\/3201234462_c0a761b898_o.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/mightyohm.com\/blog\/wp-content\/uploads\/2009\/01\/3201234462_c0a761b898_o.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/mightyohm.com\/blog\/wp-content\/uploads\/2009\/01\/3201234462_c0a761b898_o.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/mightyohm.com\/blog\/wp-content\/uploads\/2009\/01\/3201234462_c0a761b898_o.jpg?resize=700%2C400&ssl=1 2x, https:\/\/i0.wp.com\/mightyohm.com\/blog\/wp-content\/uploads\/2009\/01\/3201234462_c0a761b898_o.jpg?resize=1050%2C600&ssl=1 3x, https:\/\/i0.wp.com\/mightyohm.com\/blog\/wp-content\/uploads\/2009\/01\/3201234462_c0a761b898_o.jpg?resize=1400%2C800&ssl=1 4x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/posts\/1748","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/comments?post=1748"}],"version-history":[{"count":11,"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/posts\/1748\/revisions"}],"predecessor-version":[{"id":15844,"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/posts\/1748\/revisions\/15844"}],"wp:attachment":[{"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/media?parent=1748"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/categories?post=1748"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mightyohm.com\/blog\/wp-json\/wp\/v2\/tags?post=1748"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}