Lavry LavryBlue LE-4496 Operation Manual page 8

LavryBlue 4496
(External Clock Operation-cont.)
-There is a 2X SWITCH on the rear panel near the BNC connectors. Set the 2X SWITCH to "ON" and
the M•SYNC's HIGH/LOW switch to "HIGH" to enable the unit to receive standard sync rates while
facilitating conversion at double speed. This feature allows high-speed sampling in facilities without high-
speed sync capability.
"2X" mode works in both narrow and wide lock. In NARROW mode this means sync signals of 44.1 or 48
kHz would allow AD operation at 88.2 or 96 kHz respectively. In WIDE mode this means a sync signal in
the range of 42-50 kHz will allow conversion at twice the frequency (84-100 kHz). The front panel lamps
indicate the AES output sample rate.
The 2X SWITCH "OFF" position requires the frequency of the external sync signal and M•SYNC sample
rate switch settings to match in Narrow Mode.
FOR EXAMPLE: if you have 48kHz external word clock source, the M•SYNC module can
generate a signal at 96kHz to clock the A-to-D converter(s) when the 2X Switch is "ON," and the
M•SYNC's switches are set to "48/96," "High," "Narrow," and "Wrd Clk."
C.) M•SYNC SPECIFICATIONS
INTERNAL CLOCK ACCURACY
+/- 25 ppm (parts per million)
NARROW MODE LOCK RANGE
+/- 150 PPM for standard sample rates: 44.1, 48, 88.2, & 96 kHz.
WIDE MODE LOCK RANGE
42-50 kHz range in "LOW"
84-100 kHz range in "HIGH"
SYNC INPUT
The unit accepts an input sync signal at the rear panel BNC labeled "SYNC IN."
This can be either a standard:
Sample rate WORD CLOCK "5V TTL level" (2.5V-5V amplitude)
or an AES SYNC SIGNAL (2.5V-5V amplitude).
The input IS NOT internally terminated- please see "Regarding Termination" (below).
SYNC OUTPUT
The unit provides an output sync signal at the rear panel BNC labeled "SYNC OUT." The signal is useful
for driving another LavryBlue 4496 system (for example a multi-channel application requiring more than 8
channels of A-to-D). The output clock is a 75-ohm back terminated 3V signal (compatible with the BNC
input of the next 4496 chassis and standard WORD CLOCK inputs).
REGARDING TERMINATION
If the 4496 is the only unit being fed the Word Clock signal, connect the cable using a BNC "T" adapter
plugged into the "Sync In." On the other side of the "T", place a 75 Ohm BNC terminator connector. If the
Word Clock is "chained" using "T" connectors to other devices, be sure that there is a 75 Ohm terminator
on the "T" of the LAST device in the chain, and that none of the other devices have INTERNAL
TERMINATION. Alternately, if there is only ONE device with internal termination, it can be wired at the
"end of the chain" in place of the terminator. The important point is that there is only ONE termination and
it is located at the end of the chain.
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Operation