Fluke 54200, Руководство пользователя

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54200
Users Manual
5-46
Audio and Sound Outputs
At the
AUDIO OUT
and the
EURO AV OUT
connectors (rear side) always the sound
information of the analog FM/AM sound carrier is available. If you select
Off, 0.5 kHz,
1 kHz, or 3 kHz in the S3 Modulation popup menu the respective signals are available at
the audio outputs, which means L = R.
If you select
as NICAM
in the
S3 Modulation
popup the audio output signals correspond
to the NICAM modulation frequencies according to the S1 or S2 Modulation selection.
For details of the EURO AV OUT connector, see Chapter 3, Table 3-2.
Test 1 to Test 3 do not generate audio signals at the rear.
The digital NICAM signal is available at the NICAM OUT connectors DATA and
CLOCK .
Applications
The 54200 including NICAM sound makes it possible to check conventional TV sets
with analog sound facilities in the mono modes; furthermore, the NICAM-728 signal al-
lows you to check the complete digital sound channel in Mono, Dual, and Stereo Sound.
By selecting different NICAM amplitudes (Low or High) you can check the expander of
the NICAM decoder. In this part the scale factors are recovered and an expansion of the
audio data from 10 to 14 bits is realized.
For checking the de-emphasis of the NICAM receiver select the 0.5 / 1 / 1.5 / 3 / 12 kHz
sound frequencies. It is possible to select the RSSF bit for all NICAM modes. By doing
this, switching from NICAM to analog sound can be checked in the receiver.
Test functions
The test signals are ideally suited for checking single functions or circuitries in the sound
part of NICAM receivers, see Figure 5-32.
You can select three different special NICAM TEST signals which do not comprise real
NICAM data. They contain bit patterns to check the NICAM modules.
NICAM TEST signals:
•
TEST 1 NICAM demodulator test
•
TEST 2 NICAM decoder test
•
TEST 3 unmodulated carrier