Lake People ADC F44 Bedienungsanleitung Seite 7

When "INT"ernal was selected, with the next
switch one of two or three internal sample fre-
quencies may be selected.
As a standard F44 is equipped with 44.1 kHz,
48 kHz (and 96 kHz) oszillators.
A faulty signal on the external sync inputs is
displayed by the red "ERROR"-LED.
A valid sample-rate is shown by the green
"LOCK"-LED.
Furthermore the actual sample rate is displayed
by three yellow LED´s for the standard frequen-
cies "96, 88.2, 48, 44.1 and 32 kHz" as far as
the computed frequency is within a range of +/-
200 Hz around the above values.
Sample rates outside this window but in the
range of 28 ... 56 (108) kHz are only displayed
by the green "LOCK"-LED.
A faulty sample rate or data errors of the selec-
ted sync source are shown by the red "ER-
ROR"-LED. Simultaneously the A/D converter is
muted.
The reasons are generally:
- a week signal on the selected sync input
- unvalid data on the selected sync input
- no sync signal present
- sample-rate outside the range of 28 ... 56
(108) kHz
THE FORMAT SWITCH
The "FORMAT"-switch influences the channel
status bit of the A/D converter (see "BIT SET-
TING" table on page 10):
- Professional mode is selected when the yel-
low "PRO"-LED is lit. The channel status bits
of the digital output word from the A/D con-
verter are set to professional mode.
- Consumer mode is selected when the yellow
"PRO"-LED is not lit. The channel status bits
of the digital output word from the A/D con-
verter are set to consumer mode.
THE MUTE SWITCH
With the "MUTE"-switch a mute and recalibrati-
on of the A/D converter can be processed.
HINT:
The "MUTE"-switch does not affect any function
of the D/A converrter.
An active mute is displayed by the red "MUTE"-
LED and additionally by the red "ERROR"-LED.
A-to-D SECTION
THE ANALOG INPUTS
The analog inputs are situated on the rear pan-
el, equipped with balanced XLR connectors.
XLR pinout corresponds to AES 14-1992 re-
commendations:
1 = Ground, 2 = (+) Phase, 3 = (-) Phase
Input impedance is 5 kOhms, while input sensi-
tivity for digital full scale can be calibrated indi-
vidually for both channels within a range of +2
... +22 dBu approximately.
HINT:
To feed unbalanced signals in a proper way, pin
3 of the XLR connectors must be tied to ground.
INPUT POTENTIOMETERS
By means of two independent gain pots for left
and right channel, input sensitivity can be set
individually. Input level may vary between +2 ...
+22 dBu for digital full scale.
LEVEL METER
The level meter consists of two 10 segment
LED display for both left and right channel.
Meter range is from -25 ... 0 dB whereas 0 dB
means full scale of the A/D converter.
Dynamic law of the meter corresponds to DIN
PPM (Peak Program Meter) specifications.
Risetime for full scale is 2 msec while the re-
lease time is 1.5 sec for -20 dB signal de-
crease.
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