Real component of the complex visibility plotted against the projected baseline length in wavelengths, B_λ, for the 2004 epoch at all wavelengths between 0.7–6.1 cm. The black data points contain only VLA antenna baselines, the red data points contain both VLA and PT antenna baselines, while the green data points contain only PT antenna baselines. The dashed blue line represents the theoretical visibilities of a uniform intensity circular disk with an effective angular radius defined as .