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Calibrating The Rev. P Wind Sensor From A New Regression

I reprocessed some old data to add some software temperature compensation for the Rev. P wind sensor. The sensor itself has hardware temperature calibration built in, but the hardware compensation isn’t perfect.

You can see by these trend lines in this ADCunit vs static pressure graph that the curves diverge slightly at the upper end of the graph. I used the static pressure data from a pitot tube along with humidity and temp data, to convert the pitot tube data to wind velocities. I then set up a regression and derived an equation that matched the curve of the sensor.

I did the regression, solving for the output voltage instead of the wind speed, as I probably should have done. When the regression was done I had to factor the final equation, solving for the wind speed (in MPH) instead of for the volts, which is what the sensor outputs. This resulted in slightly less clear math, than it might have been, had I done the regression the other way around. I’m far from an expert Excel jockey, but knowing how to use the “Solver” in Excel makes me feel like at least I could play one on TV, after maybe a clean up and a shave.
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New Product: The Reverbalizer Multi-effects Module

The Reverbalizer is a hackable electronic multi-effects module for mobile and microcontroller applications. It is hackable in two ways. First, you can adapt it for use in a microcontroller project. Second, you can download or create additional DSP effects and install it on an EEPROM cartridge using an Arduino-based program we developed. It comes with 8 effects in ROM and 8 on the re-programmable cartridge.

The Reverbalizer uses the FV-1 DSP chip from Spin Semiconductor. The chip was designed by Alesis founder Keith Barr and appears in many effects units like the Z-DSP.

The built-in effects are:

  • Chorus-reverb
  • Flange-reverb
  • Tremolo-reverb
  • Pitch shift
  • Pitch-echo
  • Test (straight through)
  • Reverb 1
  • Reverb 2

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33 Amp 12 Volt Power Supplies

These are 12 volt, 33 amp switching power supplies suitable for a range of high current uses. We used them for a public art installation that we were hired to engineer and install and they performed admirably for 3 months. We powered more than 200 feet of WS2812 LED strips with a couple of these power supplies.

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