[Radioroslyn]

Well You could try tuning the bcb oscillator by monitoring it's signal in a well calibrated receiver. Use C-6 to set the osc signal heard in the well calibrated receiver at 1755kc (1300+455kc) with the dial set at 1300kc on the RCA. Same thing for the low end of the band. Use L-9 to set the osc heard in the well calibrated receiver at 1055kc (600+455kc) with the RCA dial set at 600kc. It's not uncommon to have so interaction between these two adjustment so you may have to adjust these a few times to get it on the nose. If you can't get the osc to tune from 1055 to 1755kc and your bandswitch is good and clean them I'd replace C-8 and C-11.
The other thing that comes to mind is interference from other electrical devices like cell phone/lap top chargers or computers. They use switching mode power supply and generate a lot of rf noise which can be very strong.

Terry