Thanks for the welcome. And the information.
I have a Titanium C1-PLL LNBF set up on the 120 CM dish at present, trying to sort out my satellite aim. Probably in the next couple of days I'll do some fine tuning. Then I may change it out and install the BSC621-2D C/Ku LNBF. I would really like to get C and Ku band on the same dish.
As an alternative, I still have a 90 CM GeoSat Pro dish. I may just set that up and use the switch to choose between the C and Ku dishes. Then I could keep using the Titanium C1-PLL LNBF as it gets great reception. Putting up an extra dish may strain my subdivision agreement, but they haven't noticed the 120 CM dish yet.
I made a C band LNBF adapter for my offset 120 CM dish out of flat aluminum stock that duplicated the height and angle of my plastic Ku LNBF holder.
The C band LNBF holder I got with the conical scalar wasn't tall enough to match the Ku band LNBF holder.
The adapter is rigid enough. It also doesn't destroy the original Ku LNBF holder mounts. But I still couldn't get a decent C band signal, even on G17.
Then I noticed the C LNBF didn't seem to be pointed to the same place on the dish as the Ku LNBF.
I took the Ku LNBF off and used a laser level pointer on both sides of the center of the LNBF bracket and marked where they pointed on the dish.
Then I installed my C Band LNBF adapter. I did the same marks and noticed that they were about eight inches higher than the Ku marks.
Red is the C LNBF aim point and the yellow is the LNBF Ku. Blue is the dish centerline.
Then I re-bent my aluminum adapter to achieve the same aim point as the Ku LNBF, adjusted my conical scaler and immediately got a stable signal.
So next is fine tuning the C band LNBF for aim and deciding if I want to use a second dish for Ku band.
I would probably get better signal strength for both bands that way.