On Sunday, January 6, 2013 5:13:39 AM UTC-5, Kimmo Hytoenen wrote:
I have discussed
with some variometer manufacturers about their data
communication protocols, and some of them either do not disclose
information, or do not give correct information.

That's not surprising. The vario-makers are in competition with each other, and perhaps more to the point, the early adopters of the new varios are in competition with each other.