The same approx. output indicates to me that the pressure transducers appear to be doing identical functions with changing altitude/ambient pressure. So I would normally say the problem has to be down stream of the pressure transducer output, but I'm sure Tracy has chased that rabbit. It is a puzzle
Al,
How did you go about measuring the output at different altitudes? Did you actually have wires running to some sort of ohmmeter while in flight? Or did you use a pressure chamber? If pressure (vacuum) chamber did you have a separate vacuum source on the manifold lines? Otherwise, you would not have simulated altitude accurately.
With the diodes possibly causing interference, did you run a trial jumper across the diodes and did that in fact fix the problem? Otherwise you could be barking up a long and tangled tree...
(I know, its a lot easier to ask questions than offer solutions :-)
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