Cartoon representation of spin-phase delay (δϕ_s) produced by the impact of the wind of pulsar A, with a perpendicular component to the LOS (w_⊥) for two different phases of geodetic precession: at time (t₀) and at a later time (t₀ + δt). In this representation, the observer’s LOS is perpendicular to the plane of the figure, when looking down onto it; the plane of the orbit is perpendicular to the orbital angular momentum vector, L; and pulsar A is located to the left of pulsar B. The precession of the spin axis, s, about L, proceeds along the path shown with a dashed, grey line, in the direction indicated by the arrow. The NS’s equator is shown with a solid, grey line, with the grey arrow indicating the spin direction; the magnetic axis, μ, rotates about the spin axis in the same direction. In both instances of time, the action of w_⊥ causes the deflection of the emission (assumed here to be at the magnetic pole) from position E (solid black point) to E′ (open circle). The equivalent spin-phase delay, δϕ_s at (t₀) and at (t₀ + δt), is measured as the polar angle between E and E′. For the same wind magnitude (w_⊥), it can be seen that .