  In binary radio pulsar system J0737-3039, slow pulsar B shows orbital
modulations of intensity, being especially bright at two short orbital phases.
We propose that these modulations are due to distortion of pulsar B
magnetosphere by pulsar A wind which produces orbital phase-dependent changes
of the direction along which radio waves are emitted. In our model, pulsar B is
intrinsically bright at all times but its radiation beam misses the Earth at
most orbital phases. We employ a simple model of distorted B magnetosphere
using stretching transformations of Euler potentials of dipolar fields. To fit
observations we use parameters of pulsar B derived from modeling of A eclipses
(Lyutikov and Thompson 2005). The model reproduces two bright regions
approximately at the observed orbital phases, explains variations of the pulse
shape between them and regular timing residuals within each emission window. It
also makes predictions for timing properties and secular variations of pulsar B
profiles.
