Orban OPTIMOD-FM 5700i, Operating Manual

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OPTIMOD-FM DIGITAL MAINTENANCE
4-11
D) Set the
I
NPUT
to
D
IGITAL
.
E) Connect the digital source generator to the AES3 Digital Input XLR connector
of the 5700i.
F) Set the frequency of the digital source generator to 400 Hz and its output lev-
el to 18 dB below full scale.
G) Inject the Digital Input with sample rates of 32 kHz, 44.1 kHz, 48 kHz, 88.2
kHz, and 96 kHz. Use 24-bit words.
H) Listen to the analog outputs of the 5700i and verify that the output sounds
clean and glitch-free regardless of the input sample rate.
I) Leave the digital source generator connected to the 5700i.
7. Test Digital Sample Rate Converter (Transmitters).
A) Connect an AES3 analyzer (like the Audio Precision System 2) to the AES3
Digital Output 1 XLR connector of the 5700i.
B) Set the sample rate of the digital source generator to 48 kHz.
C) Navigate to
Setup
> I/O C
ALIB
> D
IG
O
UT
C
ALIB
.
D) Change the
D
O
R
ATE
to 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, and 96 kHz, and
verify that the frequencies measured at the 5700i’s AES3 Digital Output fol-
low the values in the chart below within given tolerances:
Sample Rate Tolerance (PPM) Tolerance ( Hz)
32.0 kHz 100 PPM ±3.20 Hz
44.1 kHz 100 PPM ±4.41 Hz
48.0 kHz 100 PPM ±4.80 Hz
88.2 kHz 100 PPM
±
8.82 Hz
96.0 kHz 100 PPM
±
9.60 Hz
E) Repeat steps (A) through (D) for Digital Output 2.
F) Disconnect the digital source generator from the 5700i.
8. Test the 5700i’s synchronization capabilities.
A) Navigate to Setup > I/O C
ALIB
> D
IG
O
UT
C
ALIB
.
B) Press the
Next
button. Set the 5700i’s
P
ILOT
S
YNC
control to
R
EF
I
N
.
C) Sequentially apply a 32kHz, 44.1 kHz, 48 kHz, 88.2 kHz, and 96 kHz 1x word-
clock signal to the 5700i’s
R
EF
I
N
connector. For each sample frequency, set the
5700i’s DO R
ATE
control the same as the wordclock. Vary the frequency of the
input reference slightly and verify that the sample frequency at the 5700i’s
digital output tracks the changes you make to the reference frequency.
This test is most readily accomplished by using a synthesized function
generator with a crystal-controlled timebase. Such a generator can also
generate a 10 MHz reference signal for the next step.