JED T440 plus 439 simple system block diagram #2:
projector/no-audio & USB EWB control configuration
OR
Power amp.
+ speakers
Powered
speakers
VGA 1
(VGA 2)
Comp./S-Video
(Audio can bypass projector
and use just one channel,
with manual control. Then can
use a freeze/mute keyboard.)
Projector RS232/1
video + audio control
12 volt
plug pack
JED T440
12v
Blue: RS232
Black: VGA/Video/USB
Red: Audio
Green: PIR/Screen
PIR
detector
439 USB switcher
USB
RS232/2 control
USB-A
USB-B
USB-A
439 USB switcher does
A-B or OFF switching via
RS232 from the second
serial port to select which
computer controls the EWB
A-B USB-in
