different diameters of beads

Hi,
I want to pour two different diameters particles in simulation box, I used following script but couldn't put different diameters but just single, print-out is also given below:
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fix pts1 all particletemplate/sphere 786 atom_type 1 density constant 2460 radius constant 0.0020
fix pts2 all particletemplate/sphere 786 atom_type 1 density constant 2460 radius constant 0.003
fix pdd1 all particledistribution/discrete 6778 1 pts1 0.5 pts2 0.5
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region bc cylinder z 0 0 0.088 0.251 0.4 units box #bc block 0.0 0.239 0.0 0.239 1.2 1.5 units box
fix ins all pour/dev nparticles 75000 1 distributiontemplate pdd1 vol 0.015 50 vel uniform 0. 0. 0. 0. -3.0 region bc
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print out on screen:
Created orthogonal box = (-0.11 -0.11 0) to (0.11 0.11 0.43)
2 by 1 by 2 processor grid
0 atoms in group bed
WARNING: particledistribution/discrete: sum of distribution weights != 1, normalizing distribution
WARNING: particledistribution/discrete: sum of distribution weights != 1, normalizing distribution
particledistribution/discrete (id pdd1): distribution based on mass%:
pts1: d=4.000000e-03 (bounding sphere) mass%=100.000000%
particledistribution/discrete (id pdd1): distribution based on number%:
pts1: d=4.000000e-03 (bounding sphere) number%=100.000000%
WARNING: particledistribution/discrete: sum of distribution weights != 1, normalizing distribution

Importing STL file 'stl/int2.stl'
WARNING: particledistribution/discrete: sum of distribution weights != 1, normalizing distribution
Solid body detected in STL file
End of solid body detected in STL file.
WARNING: STL face normals were not normalized, normalizing
Mesh calculations running. This may take a while...finished!

Import of 1200 triangles completed successfully!

Particle insertion: 1622.610000 every 4609 steps, 75000 within 213034 steps
Setting up run ...
Memory usage per processor = 13.4396 Mbytes
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Best,
Ram