This read-write object selects whether the transmit spectrum is normal(0) or inverted(1). This is the transmit-side counterpart to a receiver's spectrum-inversion setting elsewhere in the chain, like an upconverter or the far-end LNB -- mismatched spectrum handling between the two ends is a common cause of a carrier that shows RF power but that the far-end demodulator can't correctly interpret. If the upconverter feeding this modem's uplink inverts the spectrum during frequency translation, an admin would set this object to inverted(1) to pre-compensate so the signal arrives at the far end with normal, non-inverted, spectral orientation.