Chapter 2—Functional Description
Model 330, 340SC and 370SC Service Manual
2-71
/LEDBL1
Brightness
/LEDBLO
Brightness
RS-232 Interface Signals
RS232 #1
RS232 #2
Description
RXD1
RXD2
Receive data
TXD1
TXD2
Transmit data
/CTS1
/CTS2
/Clear to send
/RTS1
/RTS2
/Ready to send
DCD1
Carrier detect
COMRTN
Return
IR Interface
Input
Description
/RIRIN
Input from rear IR Receiver
/EXTIRIN
Differential input from IR Receiver
EXTIRIN
Differential input from IR Receiver
/FIRIN
Input from front IR Receiver
Backplane Board p/n 100571
The Backplane is a PCB that serves as an interconnecting point for the tethered
and IR remotes, power supplies, CRTs, Yokes, ILA
®
assemblies, PCBs and
external video. The Backplane does not modify signals in any way—it merely
provides an interfacing point for most of the wiring in the projector in lieu of
cabling. Refer to Figure 2-18 for a general idea of how the wiring is
interconnected in the projector.
Backplane
CRTs,
Yokes,
Video Amps
Video and
Deflection
Signals
System
Power
Supply
Power
Control
External Video
Signals
Tethered
Remote
or PC
ILA Biases
ILAs
Opt
ica
l
PCBs
High
Voltage
Power
Supply
Power
Control