It's probably the way they do it on the automotive industry. Regards Luis On 23 Oct 2013 00:10, "Isaac Marino Bavaresco" wrote: > It is possible to use just one transducer. I have seen > transformer-coupled systems that works this way. I think it is a little > trickier to get right but also more elegant. > > > Em 22/10/2013 17:41, Brooke Clarke escreveu: > > Hi Lindy: > > > > These are raw transducers which are much harder to use than range finde= r > modules. > > for example: > > https://solarbotics.com/product/40300/ > > or > > https://solarbotics.com/product/40310/ > > > > Search eBay for ultrasonic range finder. > > > > To roll your own you need to (1) drive the transducer with a short puls= e > of 40 kHz drive and then use a second > > transducer as a receiver with a narrow band amplifier centered at 40 kH= z > then envelope detect that. The two different > > model numbers you mention have different bandwidths which determines th= e > rise and fall time of the pulse they can > > generate. The range finder modules have done all that for you and > probably for less money. > > > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .