Flying on the Cheap - Instruments

RST Engineering wrote:

Sadism & Machochism?

The problem resolves itself to dicking around with a thermocouple probe that
puts out millivolts and then picking out the microvolt rise that indicates a
rate increase. Can it be done? Sure. Easily? Perhaps. Trivially?
Probably not.

The second problem, generated by the first, is simulating such a rise and
setting the trigger in the simulation. I'm presuming that you don't want to
sacrifice an engine to calibrate the rascal. Then the question becomes,
what rate do you want to trigger? One degree a second? Ten? A hundred?
Or what rise over what time are you interested in?

Form the problem and I'll try and come up with a solution.

Jim


I see your point, Jim.
I guess the "rate" suggestion is a non-starter as it would also likely vary
considerably between engine types.

Dropping that one and looking at it as a max limit indicator would still
require rather delicate calibration, but would it be more do-able then?

The Leaf catalog doesn't mention EGT limits for the Rotax engines.
I would think a trip point just below MAX EGT (~1100 ~1200 degrees F).

There is also the issue of how and where the EGT probes are installed.
A little closer to the exhaust port will read higher and vice versa.

I dunno, Jim. I'd really like to have something like this (that works!),
but maybe I'm asking for too much?

Richard



There's been a lot of "strangeness" on the net the last few days.
Lot's of 404s and "cannot decrypt document" errors.
Is it me, or the weather still causing problems?

But this one did work...582 max egt = 1200F
FilePath=upload/techdocs/2004611123380.HM11_2.pdf