Are you sure about the call sign ?
The EME contact is just a special case of the Radar Equation
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in which the received signal is proportional to the inverse forth power of distance.
However, in this equation, the Radar Cross Section (the Moon)
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is quite large, thus, getting usable receiving power is quite possible.
With 3 m dishes (assuming 10 GHz, 3 cm) the beam width is about 0.5 degree wide and the apparent lunar diameter is also 0.5 degrees, so the antenna would illuminate the moon quite effectively.