I have been following this thread with interest as I have also been fighting to receive Classic TV at my home in Folsom, CA.
I am running a GEOSATpro DVR1100c and a GEOSATpro 90cm mounted on a GS120 motor. The dish is optimized for tracking from 58W - 148W. Until last weekend I had been using an Invacom QPH031 with a GEOSATpro DiSEqC 2x1. The Signal Quality is above threshold for the receiver and registers SQ 35% as compared to SQ 80% for 11775. On other satellites and transponders, a 35% quality will reliably lock with a 3/4 FEC, but Classic TV would not lock and would fluctuate between SQ 0% and 35%. Tried to shift the frequency in 1MHz steps and also shifted the Symbol Rate until SQ was lost. Determined the center point of each to be as published.
I first removed the 2x1 DiSEqC switch and direct connected to the linear output of the QPH031. Noted a slight increase in Signal Level, but no change n the SQ. I then removed the QPH031 and replaced with a generic sample LNBF and instantly signal lock with a stable SQ 35%. On Monday, I replaced the generic LNBF with an SL2 resulting with a stable SQ 39%. Success!!!!
Not so quick..... This morning the channels are once again microblocking and the SQ is reduced to 37%.
Maybe it is time to bring home an offset 1.8M.......