Illustration of Eq. (7) (Eq. (12) in Lee et al. 2014) for an observation at two frequency bands. The uncertainty of the infinite-frequency ToA is plotted as a function of ν₂, with ν₂ providing less precise ToAs than ν₁ (σ₂ = 5.0σ₁). All quantities are given relative to the frequency and ToA uncertainty of Band 1. On the left side of the plot (ν₂ ≪ ν₁), σ_∞ approaches σ₁, whereas on the right side (ν₂ ≫ ν₁) it approaches σ₂. This shows that the precision of the higher-frequency band is the limiting factor on the precision of the infinite-frequency ToA.