CCE HPS-1478, Руководство по обслуживанию

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HPS-1478
Condition Minimum Nominal Maximum Unit
Sep
(300Hz) L
→
R
- - - dB
Sep
(3kHz) L
→
R
- - - dB
Sep
(300Hz) R
→
L
- - - dB
Sep
(3kHz) R
→
L
- - - dB
3.1.6 Output and distortion level of S.A.P. signal for the stereo television set.
a) TV setup in PP condition.
b) Apply a 60dB
µ
V signal (frequency and channel factory defined) with 88%
video modulation, and Stereo / S.A.P audio signal carrier in accordance of
standard “MTS” (BTSC).
c) Connect an AC volt-distortion-meter at the Left channel (pin 27 – IC604)
small signal output.
Note:
ü
Disconnect the speakers for more comfortable work.
d) Adjust the Stereo/SAP generator for 400 Hz sine wave and 100%
modulation.
e) Active the SAP function in the Test Television.
f) Read Vac at the AC volt-distortion-meter.
g) Repeat all above procedures, connecting the volt-distortion-meter at the
Right channel (pin 21 – IC604) small signal audio o utput.
Minimum Nominal Maximum Unit
Output Level
- 490 - mV
AC
Distortion (THD)
- - 2 %
3.1.7 AM Rejection
a) TV setup in PP condition.
b) Connect at the IF sound input a FM generator adjust to 4.5 MHz modulated
with 400 Hz sine wave and +/- 25 kHz deviation and 90 dBuV level.
c) Connect an AC voltmeter in the audio detector output (after the emphasis
circuit) and read the VFM tension.
d) Connect at the IF sound input a AM generator pre-adjust to 4.5 MHz 40%
modulated with 400 Hz sine wave, and 90 dBuV level.
e) Read the Vam value i n the voltmeter.
AM rejection will now be calculated by the equation:
Rej
AM
= 20 log( V
FM
/V
AM
)
Note:
ü
Because this parameter is designed to define only the one circuit TV perform,
the startup conditions adjust and what’s circuits will be supplied, it will be
defined separately for each one model
.