Prism
Operation Manual Issue 2.00
Page 6.38
6.5. Channel Check (menu 5.)
The DSA-1 Channel Check mode allows continuous bit-for-bit checking of a digital
audio channel, i.e. every bit of every sample is verified to be correct. The channel may
be as simple as a cable, or as complex as a satellite link. The delay through the
channel is not relevant, and as such it is possible for the channel to be a storage
device such as a digital tape or disk recorder. If the ends of the channel are
geographically remote, the test pattern can be generated by one DSA-1 and checked
by another. The test may be run unattended, for as long a period as required, with any
errors being automatically logged both on the display and in the Results Log.
The Channel Checker can test either sub-frame (A or B channel) or both, and the check
can be made on 16-bit, 20-bit or 24-bit data. The test signal is the pseudo-random-
sequence (PRS) waveform of the DSA-1's GEN2 (see section 6.4), which is similar to
white noise at 0dBFS (full-scale) peak amplitude. The test signal contains different
data for the two sub-frames.
WARNING: The DSA-1 generator is capable of producing full-scale digital test
signals. Care should be exercised when testing systems with monitoring
headphones or loudspeakers in order to avoid personal injury or damage to
equipment.
There are two different sub-menus in the Channel Check menu, shown below, which
can be selected using the [<] and [>] keys.
5. Channel Check
[>]
5. Channel Check
5.1. Run to Log
5.2. Setup
When the desired sub-menu is displayed, press [ENTER/NEXT] to enter that sub-
menu. Alternatively, to return to the top level of the menu system, press [EXIT].
