tag:blogger.com,1999:blog-3754536133982183900.post305108526875624322..comments2023-11-02T20:40:03.333+07:00Comments on Simple Circuit Design: Simple IR Audio Transmitter CircuitFree All Tutorialhttp://www.blogger.com/profile/12784643794772489220noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-3754536133982183900.post-27718820758646655672011-04-12T06:07:48.826+07:002011-04-12T06:07:48.826+07:00what is D1 and D2? is it both of that are infrared...what is D1 and D2? is it both of that are infrared transmitter or D1 is infrared transmitter and the D2 is infrared receiver? please reply asap..tq.Unknownhttps://www.blogger.com/profile/04905604847884596796noreply@blogger.comtag:blogger.com,1999:blog-3754536133982183900.post-10514803929338882712011-02-06T17:57:40.402+07:002011-02-06T17:57:40.402+07:00Photo transistor only has 2 pins. The "third&...Photo transistor only has 2 pins. The "third" pin is internal: it's activated by the infrared light emitted by IR diodes D1 and D2.<br /><br />This circuit works, though it is sensitive to light unless you use an IR filter over Q2, and you will get a buzz over the audio output. A schmitt trigger could be useful in "squelching" that...Placedelaphoto.comhttps://www.blogger.com/profile/03471067994139068811noreply@blogger.comtag:blogger.com,1999:blog-3754536133982183900.post-20861838852913323642011-01-03T22:36:15.132+07:002011-01-03T22:36:15.132+07:00NPN photo transistor is three pins transistor.. Bu...NPN photo transistor is three pins transistor.. But you showing only 2 pins connection and 1pin where to connect.?<br />Plz Reply...Sanjeevihttps://www.blogger.com/profile/00431772285885701797noreply@blogger.com