Operation Manual

A
PPLICATIONS
ASPI Digital - The Sound of DSP Technical Support: 404.892.3200 85
A
PPLICATIONS
D
ISTANCE
L
EARNING
Distance learning classrooms are usually made up of the components shown in Figure
17, which include the EF1210 and the EF200 Phone Add.
Logic in/out for a video camera to turn to the student talker should be implemented on
the logic port of the auto mixer. Microphone muting should likewise be implemented
using the logic port of the auto mixer or muted by remote control on the EF1210 line
levels outputs. We recommend this so that the microphone is muted at the line out-
puts of the EF1210 or the input of the automixer, which allows the microphone input
to still be processed by the echo canceller in the EF1210. A useful option would be to
provide the instructor with an RS-232 remote control device that will allow the
instructor to mute student microphones using the EF1210 command set.
Figure 17. Distance Learning using the EF1210
EF1210
EF200
(Optional)
CODEC
Auto
Mixer
TO
AEC
FROM
AEC
FROM
REMOTE
TO
REMOTE
CH 1
CH 8
CH 7
CH 6
CH 5
CH 4
CH 3
CH 2
OUT 1
OUT 8
OUT 7
OUT 6
OUT 5
OUT 4
OUT 3
OUT 2
ZONE A AEC A
Instructor
microphone
Student microphones
(Push to Talk)
Logic Port
PSTN
Camera
RS-232
REC
AUX
IN
TAPE RECORDER
auto-reverse
12:00 VCR