Faria Speedo (again) - 2004 196 Limited

[TechBeer]

I also posted to the DIY articles but here is the video describing this circuit board and how to install it into your gateway. PM me if interested or ask any questions:

https://www.youtube.com/watch?v=iYaORefJk7I

[Brucetheshark]

I'm working on gauge replacement with MFD gauges. Does anyone know the paddlewheel frequency versus boat speed? It outputs a PWM where each 1/4 turn is hi or lo.

[sgregg]

TechBeer may have more specific info but as best as we could determine, it is somewhere around 4.34 - 4.61 Hz/MPH depending on which data sheet (Faria/Airmar) you look at.

[TechBeer]

It's actually not a PWM, just a simple square wave frequency to speed conversion. I know because I've been down this path with my pitot delete circuit. The Faria datasheet says 4.34 Hz/MPH which I've found to be pretty accurate, at least at speeds above about 15MPH. The Airmar ST61 is 5.3 Hz/KNT which equates to about 4.61Hz/MPH. So the 2 are fairly close.

[Brucetheshark]

It's actually not a PWM, just a simple square wave frequency to speed conversion. I know because I've been down this path with my pitot delete circuit. The Faria datasheet says 4.34 Hz/MPH which I've found to be pretty accurate, at least at speeds above about 15MPH. The Airmar ST61 is 5.3 Hz/KNT which equates to about 4.61Hz/MPH. So the 2 are fairly close.

Thank sgregg & TB, my bad on the PWM, which is to generate a voltage, whereas sq wave generates a frequency. I'm a ME, but worked with EEs just close enough to be dangerous.