  Kagome vanadates {\it A}V$_3$Sb$_5$ display unusual low-temperature
electronic properties including charge density waves (CDW), whose microscopic
origin remains unsettled. Recently, CDW order has been discovered in a new
material ScV$_6$Sn$_6$, providing an opportunity to explore whether the onset
of CDW leads to unusual electronic properties. Here, we study this question
using angle-resolved photoemission spectroscopy (ARPES) and scanning tunneling
microscopy (STM). The ARPES measurements show minimal changes to the electronic
structure after the onset of CDW. However, STM quasiparticle interference (QPI)
measurements show strong dispersing features related to the CDW ordering
vectors. A plausible explanation is the presence of a strong momentum-dependent
scattering potential peaked at the CDW wavevector, associated with the
existence of competing CDW instabilities. Our STM results further indicate that
the bands most affected by the CDW are near vHS, analogous to the case of {\it
A}V$_3$Sb$_5$ despite very different CDW wavevectors.
