SP1ML module with low distance range

Hello,

   I'm working on a project, where I need RF transceivers. I chose Your SP1ML transceiver modules, but I was dissapointed when I tried the devices, because the low distance range. The distance range abaout 20-23 m. Above this distance the devices didn't communicate with each other. I didn't find documentation anywhere, about distance range, or about register settings of this module which I can achieve the best performance.

Can You help me? Anybody tried this transceivers? What is the best distance which You can achieve?

Sincerelly,

Szabolcs Vass