RevCounter

http://www.youtube.com/watch?v=rnzVK04YmR4&feature=youtu.be

RevCounter reads, through your Android device microphone (Smartphones or Tablet ) , noise emitted from an internal combustion engine and calculates RPM. To do this,  software records sound, for approximately 1.5 seconds   from your engine and process it returning to you  RPM on your device display . After that  RevCounter records the next 1.5 seconds and proceed to another process. This process continues reading update speed  every 1.5 seconds , until the user press  "Exit" button that close the RevCounter. Decision to records every 1.5 seconds is consequent to a compromise between several factors.Resolution of 40 revolutions per minute (RPM ) ,( RevCounter is able to detect changes of 40 RPM ) it corresponds to the accuracy in  the case that engine is working with a constant speed. As mentioned above if the engine is working with a constant speed, the maximum error that you make on the RPM is just 40 RPM, while for changes of thousands of RPM in a second, the error will be about one hundred RPM . If you have largest RPM changes ,  display will showyou an average value between  maximum and  minimum RPM.
We have not found  malfunctions on any devices used to test RevCounter .
 

RevCounter is NOT able to detect  RPM from turbine .
 
If the engine noise is too weak RevCounter  may not be able to read it .



For any questions please don’t  hesitate to contact me.