Film-Tech SA10 Installation Manual page 16

Setup / Installation / 1-7
1.8.1 Cat. No. 810 Output Preamp and Backup Processor Card
This card includes the three main output sections to the power amplifiers. It also has an
input circuit that receives a mono mix of the left and right surrounds and applies this mix
to all three outputs when the backup system is active. This card also has a completely
separate power supply circuit, activated by the backup external mains transformer. The
SA10 can function normally with or without this transformer being connected to mains
power; however, if a fault develops in the main supply circuitry or any other card in the
unit, the backup system will not work if the backup transformer is not attached and
powered.
1.8.2 Cat. No. 811 Main Card – Input Switching and Decoder
This card provides all input signal switching along with Surround EX decoding of the
incoming left and right surround signals. In conventional 5.1 mode, the left and right
surround channels are passed without modification. In 6.1-channel Surround EX mode,
the information contained in the two incoming surround signals is decoded to generate the
three surround channels. The Cat. No. 811 also carries the main power supply regulators
used by all circuits in the unit. Logic interface circuitry, used to switch between
conventional 5.1-channel and 6.1-channel Surround EX mode to the host cinema
processor is located on this card.