Hi,
In the case of FUNcube the on board sensors give their readings as n bit values when they are interrogated. This data is agregated into a data frame for transmission using forward error correction to improve the s/n ratio.
The problem with on board conversion is that you would have to store the scaling/offset/logarithmic values for all channels on board, in rom.
These are usually only characterised during thermal cycling / illumination testing etc and would have to be uploaded to the satellite rom. Not necessarily a simple task.
It is easier to do it on the ground where we can tweak the calculation factors.
73
Dave, g4dpz On 9 Dec 2013 13:52, "Dave Marthouse" dmarthouse@gmail.com wrote:
I noticed over the years that satellite beacon downlinks transmit their telemetry in a form that must be translated by a telemetry app to their engineering values. Since the information is transmitted from the satellites why not provide the engineering values in the downlink without the extra step having to be done on the ground? What is the logic of doing this?
Dave Marthouse N2AAM dmarthouse@gmail.com
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb