CCE HPS-1478 - Page 9

HPS-1478
3.1.4 Áudio frequency response for the stereo television set with tonality
control
a) Repeat the above procedures (item 1.3) for the following additional
conditions:
Condition Minimum Nominal Maximum
Unit
Bass control in max. position 100Hz
- - - dB
Treble control in the meddle. 10kHz
- - - dB
Bass control in the min position. 100Hz
- - - dB
Treble control in the meddle. 10kHz
- - - dB
Bass contr. in the meddle post.. 100Hz
- - - dB
Treble control int the min pos.. 10kHz
- - - dB
Bass contr. in the meddle pos. 100Hz
- - - dB
Treble contr in the max. pos.. 10kHz
- - - dB
3.1.5 Channel separation in Stereo reception for the stereo television set
a) TV setup in PP condition.
b) Apply a 60dBµV signal (frequency and channel factory defined) with 88%
video modulation and audio stereo carrier modulation within the standard
“MTS” (BTSC).
c) Connect an AC double voltmeter at the audio output L-R.
d) Adjust the volume control to max. and the tremble, bass and balance to
middle position.
Note:
ü Disconnect the speakers for more comfortable work.
e) Adjust the stereo generator for left channel only – with 30% modulation of
300 Hz sine wave and 7.5 kHz deviation.
f) Read the Double Voltammeter value Vac corresponding of Left and Right
channel and calculate the stereo separation trough the equate:
Sep
(300Hz) L→R
= 20 log (V
L
/V
R
)
g) Adjust the stereo generator for left channel only – with 30% modulation of
3kHz sine wave and 7.5 kHz deviation.
Sep
(3kHz) L→R
= 20 log (V
L
/V
R
)
h) Repeat the procedures e, f and g, and now select Right channel only, at the
same conditions above mentioned.
Sep
(300Hz) R→L
= 20 log (V
R/
V
L
)
Sep
(3kHz) R→L
= 20 log (V
R/
V
L
)