A newly bought LNB doesn't work with my old CCTV box

I just bought a LNB to replace my old one, but it doesn't work. I am not sure if it is a correct LNB. 

My CCTV box settings: 11780 H, 20760, LNB 10.750 GHZ (these cannot be changed)
The new LNB: Input 10.7-12.75 GHZ; Output 950-2150 MHZ, Noise Figure 0.3dB.

My old LNB still works but the signal quality is not good (about 75). I replaced it with the new one and there was no signal (signal quality) at all though the signal power is strong (197). 3 years ago, I bought the old LNB and it worked immediately after I installed it. I didn't adjust the dish at all.

Please advise me if I bought a wrong LNB this time.  I tried to adjust the dish, but could not get signal with the new one. After I put the old LNB back, I could get the signal (about 75).

Thanks!

所有跟帖： 

• Have you moved the dish or new LNB to see if -st.paul- ♂ (305 bytes) () 05/01/2014 postreply 17:08:12

• I did all you said, but I could not see any signal with the new -don2002- ♂ (132 bytes) () 05/01/2014 postreply 17:17:32

• Is the 78 from new or old one? -st.paul- ♂ (0 bytes) () 05/01/2014 postreply 17:37:55

• From the old one. The new one has no signal. -don2002- ♂ (119 bytes) () 05/02/2014 postreply 10:23:38

• I bough this one from ebay and it works -st.paul- ♂ (289 bytes) () 05/02/2014 postreply 10:49:43

• Amazon shipped me another one with Ku band. It will arrive tomor -don2002- ♂ (80 bytes) () 05/02/2014 postreply 12:18:15