tag:blogger.com,1999:blog-8263330246108578452011-08-01T17:57:21.096-07:00The Past dayhttp://www.blogger.com/profile/12531664881508792781noreply@blogger.comBlogger51100tag:blogger.com,1999:blog-826333024610857845.post-55424288389510896682009-11-30T23:29:00.000-08:002009-11-30T23:32:34.851-08:00This is a circuit where a microphone and preamp circuit (voice circuit) have priority over any other audio signal. You can think of this as a one way intercom, if the main amplifier is used for listening to music, then when the push to talk switch is pressed, the amplifier is switched to the voice signal.<br /><a href="http://4.bp.blogspot.com/_ZQcyIDLbx30/SxTGM-02UlI/AAAAAAAAAB8/oHDqOYXWL0M/s1600/voiceover.gif"><img id="BLOGGER_PHOTO_ID_5410166978704200274" style="DISPLAY: block; MARGIN: 0px auto 10px; WIDTH: 275px; CURSOR: hand; HEIGHT: 148px; TEXT-ALIGN: center" alt="" src="http://4.bp.blogspot.com/_ZQcyIDLbx30/SxTGM-02UlI/AAAAAAAAAB8/oHDqOYXWL0M/s200/voiceover.gif" border="0" /></a> Full Circuit and Part List <a href="http://www.zen22142.zen.co.uk/Circuits/Audio/v_over.htm">zen22142.zen.co.uk</a><br /><div></div><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/826333024610857845-5542428838951089668?l=audio-circuits-diy.blogspot.com' alt='' /></div>The Past dayhttp://www.blogger.com/profile/12531664881508792781noreply@blogger.com0tag:blogger.com,1999:blog-826333024610857845.post-54680461607914999452009-11-30T23:24:00.000-08:002009-11-30T23:28:14.369-08:00Here is a simple and cheap amp to make<br />I could have made the circuit board smaller but "what the heck"<br /><br /><p><img style="DISPLAY: block; MARGIN: 0px auto 10px; WIDTH: 311px; CURSOR: hand; HEIGHT: 264px; TEXT-ALIGN: center" alt="" src="http://europa.spaceports.com/~fishbake/amp/ampc.JPG" border="0" /></p><p>Full Circuit and Part List <a href="http://europa.spaceports.com/~fishbake/amp/ca100.htm">europa.spaceports.com</a></p><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/826333024610857845-5468046160791499945?l=audio-circuits-diy.blogspot.com' alt='' /></div>The Past dayhttp://www.blogger.com/profile/12531664881508792781noreply@blogger.com0tag:blogger.com,1999:blog-826333024610857845.post-87220527869003677612009-11-30T23:06:00.000-08:002009-11-30T23:24:14.440-08:00<div><div><div><div>A simple mixer with 3 line inputs and 3 mic inputs using commonly available parts.</div><br /><br /><img id="BLOGGER_PHOTO_ID_5410164839380797074" style="DISPLAY: block; MARGIN: 0px auto 10px; WIDTH: 400px; CURSOR: hand; HEIGHT: 246px; TEXT-ALIGN: center" alt="" src="http://1.bp.blogspot.com/_ZQcyIDLbx30/SxTEQdOZxpI/AAAAAAAAAB0/tX-nbi5u6tg/s400/6ipmix.gif" border="0" /><br />The mixer circuit above has 3 line inputs and 3 mic inputs. The mic inputs are suitable for low impedance 200-1000R dynamic microphones. An ECM or condenser mic can also be used, but must have bias applied via a series resistor. </div><div> </div><div>Full Circuit and Part List <a href="http://www.zen22142.zen.co.uk/Circuits/Audio/6ipmix.htm">zen22142.zen.co.uk</a></div></div></div><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/826333024610857845-8722052786900367761?l=audio-circuits-diy.blogspot.com' alt='' /></div>The Past dayhttp://www.blogger.com/profile/12531664881508792781noreply@blogger.com0tag:blogger.com,1999:blog-826333024610857845.post-49775308274939776742009-11-30T22:57:00.000-08:002009-11-30T23:04:27.013-08:00<div align="center"><strong>Subwoofer Equaliser </strong><br /></div><div align="center"><strong>(Using The Linkwitz Transform Circuit) Rod Elliott (ESP)</strong></div><div align="left">The Linkwitz transform circuit is a hugely flexible way to equalise the bottom end of a sealed loudspeaker enclosure. Unlike the original "EAS" (Electronically Assisted Subwoofer) project or the ELF™ systems, a speaker that is corrected using this method is flat from below resonance to the upper limit of the selected driver. The low frequency rolloff point is determined by the parameters of the transform circuit. Should the enclosure size be too small and cause a lump in the response before rolloff, this is also corrected. A conventional active crossover network is then used to divide the subwoofer signal from the main channel signals.</div><div align="center"><strong></strong></div><div align="center"><strong></strong></div><div align="center"><strong><img style="DISPLAY: block; MARGIN: 0px auto 10px; WIDTH: 446px; CURSOR: hand; HEIGHT: 222px; TEXT-ALIGN: center" alt="" src="http://sound.westhost.com/p71-pic.jpg" border="0" /></strong></div><br /><p>For a detailed look at how the circuit works, please click here to see the article that describes the operation of the circuit.</p><p>For Full Circuit Please see <a href="http://sound.westhost.com/project71.htm">http://sound.westhost.com/project71.htm</a></p><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/826333024610857845-4977530827493977674?l=audio-circuits-diy.blogspot.com' alt='' /></div>The Past dayhttp://www.blogger.com/profile/12531664881508792781noreply@blogger.com0tag:blogger.com,1999:blog-826333024610857845.post-87199035593525380862009-11-30T22:51:00.000-08:002009-11-30T22:54:14.448-08:00circuit with balanced input and adjustable gain to drive needle type VU meter, uses special amplifier module from Op-Amp Labs<br /><br /><a href="http://www.opamplabs.com/audlvlmt.jpg"><img style="DISPLAY: block; MARGIN: 0px auto 10px; WIDTH: 525px; CURSOR: hand; HEIGHT: 204px; TEXT-ALIGN: center" alt="" src="http://www.opamplabs.com/audlvlmt.jpg" border="0" /></a><br /><div>More Detail and Part list <a href="http://www.opamplabs.com/audlvlmt.htm">opamplabs.com</a></div><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/826333024610857845-8719903559352538086?l=audio-circuits-diy.blogspot.com' alt='' /></div>The Past dayhttp://www.blogger.com/profile/12531664881508792781noreply@blogger.com0