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   Parabola Calculator version 2.0
  </title><meta content="Parabola, Parabolic, Equation, Calculator, parabolic trough calculator, Solar, Collector, wifi, reflector, focal length, f/D, feedhorn angle, offset dish"name=Keywords><meta content="This Freeware program was written to help you design solar or wifi projects using Parabolic Reflectors. This program will calculate the focal length and (x, y) coordinates for a Parabola of any diameter and depth. It can help you determine what size and shape to make your parabola very quickly."name=Description><meta content=mscir@yahoo.com name=Contact><meta content="Mike Scirocco"name=Author><style>* {
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}</script><div style="background:#DFDCCF; border-bottom:1px solid #393939; position:relative; z-index:999999999!important"id=tb_container><style>.adCenterClass{margin:0 auto}</style><div style="display:block!important; overflow:hidden; width:916px;"class=adCenterClass id=tb_ad><div style="display:block!important; float:left; width:728px"id=ad_container><script>if (typeof lycos_ad !== "undefined" && "leaderboard" in lycos_ad) {
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}</script><div style="background:#DFDCCF; border-top:1px solid #393939; clear:both; display:none; width:100%!important; position:relative; z-index:999999!important; height:90px!important"id=FooterAd><div style="display:block!important; overflow:hidden; width:916px;"class=adCenterClass><div style="display:block!important; float:left; width:728px"id=footerAd_container><iframe style="border:0; display:block; float:left; height:96px; overflow:hidden; padding:0; width:750px"id=lycosFooterAdiFrame></iframe></div></div></div><div id=wrapper><h2>Parabola Calculator version 2.0</h2><div class=imgdiv><img alt="Small Version of Main Program Window"height=200 src=images/0.gif width=398></div><div class=contentdiv><h4>About This Program</h4> This Freeware program was written to help you design solar collector or wifi projects using parabolic reflectors. Whether you're improving the signal strength of your wifi antenna, or designing a satellite antenna or solar trough, this program calculates the focal length and (x, y) coordinates for a parabola of any diameter and depth. It can help you determine what size and shape to make your parabola very quickly. Version 2 includes Wifi calculations for centered or offset feedhorn dishes. If you would like modifications to the program to make it more useful to you or to send feedback, you can email me <a href=mailto:mscir@yahoo.com> here </a> . <h4>Credits</h4> Thanks to <b> Frank Schindler </b> for the curve fitting code used by this program, you can see his page <a href=http://www.codeguru.com/vb/gen/vb_misc/article.php/c2729/ target=_blank> here </a> . <p>Thanks to <b> Bernhard S. Müller </b> for helping develop and beta testing version 1, you can see his site <a href=http://www.mueller-solartechnik.com/ target=_blank> here </a> .<p>Thanks to <b> Edisher Giorgadze </b> for helping develop and beta testing version 2, you can see his page <a href=http://www.amsatnet.com/p5.html target=_blank> here </a> .<p>Thanks to <b> Paul Wade </b> for supplying the WiFi text, calculations and code, they were copied directly from his hdl_ant program, you can visit his site and download his program <a href=http://www.qsl.net/n1bwt/ target=_blank> here </a> .<h4>Download the Program</h4><p>This program was written in Visual Basic 6, and should run on Window 95 or later. The program will run under Linux using Wine if you copy the dependancy files into the folder where the program resides. The program requires Visual Basic 6 runtime files, your computer may already have them installed. I would try downloading the smaller file (program only) first and seeing if it runs. If not, delete it and download the Windows Installer to perform a standard Windows installation.<ul><li><a href=parabola2.zip> Download Parabola.exe (137 kB) </a> (program only, does not include Visual Basic runtime files)<li><a href=parabola2_installer.zip> Download Windows Installer (1.65 MB) </a> (run Setup.exe to perform standard Windows installation)<li><a href=parabola2_vb6_sourcecode.zip> Download VB6 Source Code (155 kB) </a><li><a href=parabola2_linuxfiles.zip> Download VB6 runtime files for Linux Wine (740 kB) </a></ul><div id=translate><script src=http://www.altavista.com/static/scripts/translate_engl.js></script></div><div id=donate><form action=https://www.paypal.com/cgi-bin/webscr method=post target=_blank><input name=cmd type=hidden value=_s-xclick><input name=hosted_button_id type=hidden value=5059033><input alt="PayPal - The safer, easier way to pay online!"name=submit src=https://www.paypal.com/en_US/i/btn/btn_donateCC_LG.gif type=image><img alt=donate border=0 height=1 src=https://www.paypal.com/en_US/i/scr/pixel.gif width=1> If you find this program useful and want to support program development, I accept small donations. <br> Thank You.</form></div><h4>Links</h4><a href=http://solaractionalliance.org/ target=_blank> Solar Action Alliance </a> exists to educate visitors and provide them with opportunities to get involved with solar. This includes a petition, a blog full of informative articles, location-specific solar infographics, and much more! <br><a href=http://www.mueller-solartechnik.com/ target=_blank> Bernhard S. Müller's SolarTechnik.com </a><br><a href=http://cuisson-solaire.over-blog.fr/ target=_blank> La Cuisson Solaire </a><br><a href=http://recombinantdesign.com/ target=_blank> Welcome to ReCombinant Design! </a><br><a href=http://solarcooking.wikia.com target=_blank> The Solar Cooking Archive Wiki </a><br><a href=http://solarcooking.wikia.com/wiki/Parabolic_solar_reflectors target=_blank> The Wikia Parabolic Solar Reflectors Page </a><br><a href=http://www.qsl.net/n1bwt/ target=_blank> Paul Wade's N1BWT 10 GHz Page </a><br><a href=http://www.thirdparadigm.org/ target=_blank> The Third Paradigm (OT) </a><h4>Program Notes</h4><p><span class=bignum> 1. </span> When you run the program you will see the main program window shown here. Use any units you like, as long as you use the same units for both the Depth and Diameter. You can also select Diameter and f/D as inputs using the <span class=alert> Options > Select Inputs </span> menu choice. I recommend using smaller units: inches instead of feet, or millimeters instead of meters, to increase the resolution of your measurements.</div><div class=imgdiv><img alt="Main Program Window"height=381 src=images/1.gif width=760></div><div class=contentdiv><span class=bignum> 2. </span> After you enter some numbers into the Diameter and Depth text boxes and click the <span class=alert> Calculate </span> button, the program will show you the scaled down shape of the parabola you described, and it will calculate the (x, y) coordinates of the curve of the parabola in 16 straight line segments. You can calculate the (x, y) coordinates using anywhere from 2 to 1000 segments.</div><div class=imgdiv><img alt="Enter Inputs into Main Program Window"height=381 src=images/2.gif width=760></div><div class=contentdiv><span class=bignum> 3. </span> To see what the shape and focal length would look like when the depth is increased to 18, hold down the horizontal scroll bar next to the text box and watch the parabola's shape change.</div><div class=imgdiv><img alt="Change Inputs in Main Program Window"height=381 src=images/3.gif width=760></div><div class=contentdiv><span class=bignum> 4. </span> If you click the <span class=alert> Save to Text File </span> button, the program will prompt you to select a folder and enter a filename, and then it writes a file with the information you see in the text box on the right. Here's how the saved file looks when it is opened using Windows Notepad (using the Lucida Console <a title="Read about non-proportional fonts at Wikipedia"href=http://en.wikipedia.org/wiki/Typeface#Proportion target=_blank> non-proportional </a> font where all characters have the same width so the columns line up vertically). The program will automatically suggest a filename that includes depth and diameter but you can enter any filename you like.</div><div class=imgdiv><img alt="Saved Text File"height=348 src=images/4.gif width=339></div><div class=contentdiv><span class=bignum> 5. </span> If you'd like to see the coefficients of the Equation that describes the current Parabola, use the menu choice: <span class=alert> File > View the Coefficients. </span> You will see a message box like this one showing you the values used in the parabola equation:</div><div class=imgdiv><img alt="Menu Choice to see Parabola Coefficients"height=357 src=images/5.gif width=275></div><div class=imgdiv><img alt="Parabola coefficients"height=263 src=images/5a.gif width=404></div><div class=contentdiv><span class=bignum> 6. </span> If you move your cursor over the image of the parabola, you will see the individual points calculated by the program: the (x, y) coordinates are shown at the bottom of the display. The point (horizontally) closest to the mouse cursor will be shown, you can see the location of each point listed in the text box.</div><div class=imgdiv><img alt="Viewing the (x,y) coordinates on the Graphic"height=381 src=images/6.gif width=760></div><div class=contentdiv><span class=bignum> 7. </span> There are several file output formats you can use to save the data to a file that can be read by another program like ACAD, CorelDraw, or MS Excel. You can see these menu choices under the <b> File </b> menu. <p>You can print the graphic of the parabola to a printer using the <b> Print </b> menu choice.<p>You can change the foreground and background color of the Parabola graphic using the <b> Options </b> menu choice.</div><div class=contentdiv><span class=bignum> 8. </span> Wifi Calculations for centered or offset feedhorn dishes can be done using the <span class=alert> Wifi Calculations </span> menu choice.</div><div class=imgdiv><img alt="Wifi Centered Feedhorn Calculations"height=190 src=images/centeredfeedhorn.gif width=712><br><br><img alt="Wifi Offset Feedhorn Calculations"height=548 src=images/offsetfeedhorn.gif width=550></div><div class=contentdiv><span class=bignum> 9. </span> If you'd like to read more about Solar Collectors and Solar Cooking Projects, or about the math behind Parabolas, click the menu choice: <br><span class=alert> File > Parabola and Solar Project Websites </span> . <br> Click on a website and it will load into your default web browser automatically. Click the <span class=alert> Hide </span> button to view the main program form again when you're finished with the web sites. <a href=solar_links.htm> A collection of these links can be found here. </a></div><div class=imgdiv2><img alt="Web Sites About Parabolas"height=381 src=images/8.gif width=760></div><p> </div><script>var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));</script><script>try {var pageTracker = _gat._getTracker("UA-12082628-1");
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