This is a question we see frequently.
Typical Local Oscillator frequencies for LNBFs
Standard KU (11.7-12.2 GHz)
LO: 10750
Universal KU (10.7-12.75 GHz)
LO low: 9750, LO Hi: 10600
DSS LNBF (12.2 - 12.75 GHz)
LO: 11250
Anytime you swap LNBFs, make sure your MPEG2 receiver is setup with the correct LNBF LO freq. as above.
Also, make sure you are using a LIVE trasnponder for checking signal and quality. If one transponder is not working, try another one. 12152 is a strong transponder on T5, for example.
Best of luck
