Fluke 54200, Руководство пользователя

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54200
Users Manual
5-54
Test 3
Mono: L = R = 300 Hz
With a level of '75 µs EIM of 100%' which corresponds to 99% audio input level. The
L+R signal modulates the sound carrier with the maximum allowed peak deviation
(
∆
fmax = 25 kHz for L+ R).
SAP: fmod = 300 Hz
With a level of '75 µs EIM of 100%'. The SAP carrier is now modulated with the maxi-
mum allowed peak deviation (
∆
fmax = 10 kHz).
Both signals, the Mono- and the SAP signal are useful to adjust a BTSC-decoder to its
approximately maximum output level or to compare the Mono signal level with a corre-
sponding SAP signal.
Applications
The 54200 with BTSC makes it possible to check TV sets with analog sound facilities in
Mono and BTSC. The BTSC facilities allow performance measurements and alignment
of TV receivers and VCRs in regard to the BTSC Stereo and SAP processing.
For baseband processing the composite signal is available at the MTS/PILOT Output.
The output level of the MTS Output is about 930 mV rms (open circuit) for the maxi-
mum L+R signal. This maximum level for L+R is available using Test 3 and corre-
sponds to a peak deviation of
∆
f = 25 kHz of the sound carrier. For nominal L+R level
(
∆
f = 13.5 kHz) the MTS output level is 500 mV rms (open circuit).
By connecting the MTS Output directly to a BTSC decoder, you have to change the out-
put level to the specified input level of the used decoder.
The MTS Input is available to apply an external BTSC composite signal so the 54200 is
used as an RF modulator.
Areas of application:
•
Alignment of the composite input level.
Alignment of FM-sound-demodulator-output level,
(for instance using Test 3).
•
Alignment of Stereo channel separation of BTSC decoders.
Settings of 54200 for BTSC Stereo separation:
TV system: NTSC M or PAL M
Video modulation: OFF (Video Extern),
or black pattern (black-burst signal),
all patterns turned off
Sound carrier: ON