The IQmonitor program allows you to receive signals outside the LNB frequency range
at the 3rd and even 5th harmonics of the PCI card local oscillator.
So for TBS 6983, reception is theoretically possible up to a frequency of 2.4 x 3 + 10.6 = 17.8 GHz,
but is practically limited by the frequency properties of transistors and microcircuits
Practically LNB Inverto Black Ultra is operable up to frequencies of the order of 13.5 - 14 GHz.
Need to try