The 1.3.0.4 version of SIFMPRO is available as a free download on our website. SIFMPRO lies within Office Tools, more precisely Calculators. This free program is an intellectual property of Sennheiser/SDA. Our antivirus analysis shows that this download is virus free.
From the developer:
SIFM is the Sennheiser Software for rapid calculation of intermodulation-free radio frequencies for wireless microphone systems.
Interference due to intermodulation generally occurs when at least two transmitters close to the receiving antenna produce very strong signals in the receiver. The two signals form intermodulation products at non-linearities, such as transistors or other semiconductors in the receiver (e.g. in the mixer).
You may want to check out more software, such as ProCalc, WorldCalc or DBF to CSV Conveter, which might be similar to SIFMPRO.