Sonifex COURIER, Руководство пользователя

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Chapter 12 - connectivity
Courier User Handbook 12-16
When making the frequency selection you have to be aware that you only have a
certain amount of bandwidth across the ISDN line. Courier uses a single B channel
of the ISDN pair, i.e. 64kbps maximum. You have to make the decision of which
needs to be better, the quality or the bandwidth.
Quality - If you choose the transmission to be of 48kHz, you will hear the
higher frequencies but there may be more artificial artifacts
introduced by the mpeg encoding process.
Bandwidth - If you select a 24kHz transmission you will find that there will be
fewer artifacts, but you will not have the full range of the higher
frequencies, thus loosing some of the quality. Generally, when
using a 64kbps ISDN line, selecting 24kHz as the sample rate
will give a better perceived performance. Most codecs support
24 and 48 kHz, but Telos devices do not support 24 kHz so use
32 kHz instead.
This menu also allows you to choose if you wish to have CRC switched on (which
may be a requirement of the codec that is decoding the audio).
The [End Play Beeps] option is for use when playing a pre-recorded cut over a live
ISDN link. To warn you when the cut is about to finish, with this option enabled,
the Courier emits three beeps at one second intervals for the last three seconds of
the cut.
To exit this menu once you have made your decisions select [Close].
12.4.2. Transferring data files over ISDN
The internal ISDN modem can be used to transfer data files over a single ISDN B
channel, at 64kbps. Simply use the supplied ISDN cable to connect the ISDN line
directly to the Courier. At the other end of the ISDN line, you just need a suitable
ISDN modem to receive the data file.
The procedure is exactly the same as for dialling using a standard modem, except
that the PhoneBook entry for each number using ISDN should refer to [ISDN
Internal] instead of [Ext. Modem].
See Chapter 11 for information on the PhoneBook and see sections 12.2.2.1 to
12.2.2.3 for information on dialling.