Marantz 3800 - Page 25

-10 dB
—20 dB
—30 dB
—40 dB
—50 dB
al
ye DOLBY LEVEL
‘hai
_—o
L_i |
0 100 200
Figure 2-8 Dolby Frequency Response, Flat Mode
F.
(1)
2-10
(c)
(d)
(e)
Check frequency response for oscil-
lator frequencies from 20 Hz to 15
kHz. Response should be flat (+
1.5 dB).
Reset oscillator frequency to 100 Hz
and lower the amplitude by 30 cB.
The signal level at the TAPE OUT-
PUT Jacks should be approximately
18 mV rms.
Reset oscillator frequency to 5 kHz
and observe output level. Output
level should drop 9 dB (+ 2 dB) or
to a level between 5.1 mV and 6.5
mV rms.
DOLBY PLAYBACK MODE FREQUENCY
RESPONSE ( Figures 2-8 through 2-10 )
(a)
(b)
When decoder functions as a flat amplifier:
Ensure all controls are set as listed
for Decode Loop Gain, Paragraph 3D.
Apply a 1 kHz signal to the AUX
INPUT Jack and adjust amplitude for
O VU indication on the Dolby VU
Meter.
(2)
(c)
(d)
(e)
oo
2000 5000 10000 20000
NOTE: Meter indication of 0 VU
corresponds to an output level of
approximately 6.3 V rms as mea-
sured at the PREAMP OUTPUT Jack.
Check frequency response for oscil-
lator frequencies from 20 Hz to 15
kHz. The output signal as measured
at the PREAMP OUTPUT Jack should
be flat (+ 1 dB).
Lower input signal level 30 dBto an
output level of 200 mV rms as
measured at the PREAMP OUTPUT
Jack.
Check frequency response for oscil-
lator frequencies from 20 Hz to 15
kHz. Response should be fht (+
1 dB).
When decoder functions as a decoder:
(a)
(b)
Ensure all controls except lolby
Switch are set as listed in Paray-aph
3D. Reset Dolby Switch to PLAY.
Apply a 100 Hz signal to the XUX
INPUT Jack and adjust the ampitcude