Setting The Aes Reference - Pl - pro bel Freeway Manual

Freeway Range Pro-Bel ltd
• 3.8 Setting the AES reference - PL 17
In order to perform click-less switching of digital audio signals, a cut must be
made during a point in the data stream when no audio is present (usually during a
pre-amble). For this to happen, the switcher must receive a digital audio reference
signal synchronous with the audio signals arriving at the frame.
Note that an audio cut is performed at the first appropriate instant following a
television field boundary (as derived from the video reference input).
The Freeway router can be con figu red to accept an unbalanced digital audio
signal as a reference, in wh ich case a dummy 09 connector must be fitted. Th e
diagram below illustrates the necessary installation details .
AES REF
SK2 7
AES+ U
(UNBALANCED)
2
a
'"
NOTE
N
"
RJR UNBALANCED REFERENC E
INPUT - LIN K PINS 2 AND 4 .
6 AND 7 ON PL 17 (AES REF)
MAnNG CONNECTOR
PLl 7
~
,
AES ,·
2
AES+U
NlC
3
4
5
] I.INK
AES
AES­
6
7
~
LIN K
REF
NIC 8
NlC 9
10
11
' - - ­
"
~
LIN K FO R
UNBAlANCED AES
REFERENCE IN PUT
6540T-00 Nov 97 24