EFIS systems use as encoder

I know some of you are using or planning to use the gray code (or serial - Thanks Paul) output of the GRT and other EFIS systems to provide the "encoder" data for the transponder.

I ran across this today and figured, I'd cross post a link to it. It appears that the FAA has issued some form of letter that disapproves of this approach. It further appears that there is a grass roots effort to change that ruling. I do not know where it stands currently.

Similar to this whole 51% rule that is currently being investigated by the FAA, it appears that some other parts of the experimental community are also being reviewed and ruling issued.

http://lists.matronics.com/viewtopic.php?t=13014

FWIW,

Interesting....

Interesting Alan - I agree with the poster that we should not make a big deal out of it (at least not for awhile...). I have found so many differences of opinion between FSDO's (and between FSDO's and HQ's) over the years, that I rarely take anything as a "final" opinion!

BTW, if you're using a GRT as a source, you're using the Serial data - the Gray code doesn't work right (last I heard, that was still the case).