I asked the question regarding the sat file for the following reason :
I use a Bullseye LNB that I don't want to modify. To bring back the QO-100 frequencies in the range of the SF8008 tuner, I use a converter called SUP-2400 (https://home.swissatv.ch/2013/12/lnb-avenger-et-convertisseur-sup-2400/) .
Unfortunately it reverses the frequency...
IN 250-750 MHz OUT 2150-1650 MHz LO 2400 MHz
So your plugin will be the place once working to modify to do the math for me !
73 qro de michel, hb9dug