Telos ZephyrExpress user manual Dual Site Operation, Layer 2 Mono64kpbs vs MONO128 Dual vs Jstereo

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IMPORTANT!

The Layer 3 decoder in L3 STEREO mode requires that both ISDN lines be connected and operating in order for the decoder to function. Until both lines are present, the decoder will not output anything, even if the transmission mode at the distant studio is not stereo. Any data drop outs would cause interruption in both audio channels.

If your application requires the ability for the two channels to come and go independently, such as when they are from independent sites, you must use G.722 That is the only decode mode which supports fully independent operation.

Dual Site Operation

It is possible to use the dual mono transmit mode to send to two receivers at different sites. Set the transmit mode to L3-DUALand dial Line 1 at each site.

wThis topic is covered more thoroughly in section 7 (Menu Reference). Receive, if used, must be set to the G.722 mode. The Layer II/III decoder is unable to accommodate the independent signals.IMPORTANT!You must make the call to the telephone number for Line 1. The mono Layer 2/3

decoder will work only with signals coming in on the first line.

Layer 2: Mono64kpbs vs MONO128; Dual vs JSTEREO

cWith one transmission path,

• The only usable L2 setting is monaural, at 64kbps (L2 MONO64).COMPATIBILITY TIP!Layer 2 Mono64 is called simply Layer 2 Mono on Zephyr.

With two transmission paths,

•L2 MONO128 provides the best Layer 2 quality by combining both transmission paths to achieve a higher bitrate. This mode requires 2 data paths, or both ISDN lines.

c• L2 STEREO mode is simply two simultaneous mono channels, with compensated delay to preserve phase. Fidelity is identical to L2 MONO64, since the algorithm can’t take advantage of redundancy between the channels.COMPATIBILITY TIP!Layer 2 Stereo is called Layer 2 Dual on some systems.

CODING 5-13