Marantz SR-3000, Service Manual

Page: 41 / 77

8-4 8-4
Change time delay to 15 msec (only in versions with variable delay).
he surround pulse in channel B moves to the left with respect to side from center marker (channel A) position.
Change time delay to 25 or 30 msec (versions with variable delay).
The surround pulse in channel B moves to the right with respect to center marker (channel A) position.
Time delay with track 6
Alternative methode :
The functional operation of the time delay can be made visible with a lisajous figure, with an single beam scope.
Connect X-direction on Surround output
Connect Y-direction on Left or Right output/input.
Note : be careful and use only 1 ground connected to scope.
Select track 6 (surround test) :
Make the lisajous figure visible on the scope (amplitude adjust) see fig. 4
Lisajous out of phase
Fig 4Time delay = OK
Note :
in sets with variable time delay the ellipse of the lisajous figure must be always open. Changing the
time
delay changes the direction of the circle accordingly
.
CHANNEL modes
:
Surround OFF (Stereo) 2 channel mode
Signal on :L out (2703) and R out (2704)
Surround ON
-Prologic 4 channel mode all four outputs are used
Signal on : L out (2703), R out (2704), Center out (2705), Surround (2706).
-Front 3 stereo No surround speaker available
The surround information is equelly to the left and right outputs.
Signal on : L out (2703), R out (2704), Center out (2705).
-HALL
Signal on : L out (2703), R out (2704), Surround (2706).
Subwoufer out . not in all versions
Signal on : Subwoofer out (2788).
(....) as indicated on the component side of the DPL decoder board.
15 msec.
25 msec.
20 msec.
1 msec = 1
kHz
20
m
sec
20
m
sec
20
m
sec
40
m
sec
30
m
sec
30
m
sec
25
m
sec
25
m
sec
15
m
sec
15
m
sec
L
t
Surrou
n
d
Amplifier Output Center Amplifier Output
Rt
Result i
n
Center / Surro
und cha
n
n
e
l
Encode
d
signaal
!
No T
im
e Dela
y
!
No T
im
e Dela
y
Marker
Marker
D C B A
Surrou
nd 18
0˚
I
n
fo
Surrou
nd 18
0˚
I
n
fo
Surrou
nd 18
0˚
I
n
fo
Center 0˚
Info
Center 0˚
Info
Center 0˚
Info
Fig 1
fig 1d fig 1c fig 1a fig 1b