Profile variation with respect to orbital phase. Left: black lines indicate the integrated profile of L-band data summed from 25 eclipses for orbital phases 89° < ψ < 91° with an interval of Δψ = 0.25°. The baseline of the profile is placed at the centre of each interval, and the numbers on the right side of the profiles (np) indicate the estimated upper limit for the number of pulses in that interval. The red curves indicate the reference (standard) profile integrated over a 2 h observation excluding the eclipse part. Right: residuals of the added profile with respect to the reference profile.