The smart pressure sensor is the key to this
compression tester. It is a smart sensor in
that it puts out zero to five volts making
it compatible with the Maximite analog to digital
input pins.

It cost about $50 at mouser. About the same price as
the Maximite :-)

The Maximite program to read  and record it many times a
second  shortly.

Paul Lamar

Here it is along with the pressure sensor wiring.
Data is in atmospheres I think.
Data is printed on the screen but it would normally go to a file
on the SD card. It is comma delimited so it can be loaded
into a spread sheet and plotted.

The hard ware interrupt comes in every 200 ms or 5 times a second.
Could be up to 1000 a second or 1 ms. There is lots of space on
that 32 gig SD card :-)

Super simple.

Paul Lamar


The barometric pressure is up this morning.
I added time and date to the file from the battery backed
up clock  as well as labeling it rotor 1.

For the EFIS version you could calculate density altitude.

Paul


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