Harman Kardon AVR 7000, Руководство по обслуживанию

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harman/kardon
Service Bulletin
Service bulletin # H/K2002-06 October 2002 Warranty labor rate: MINOR repair
To: All harman/kardon Service Centers
Model: AVR7000
Subject: Low or No Output from Subwoofer Output Jack
In the event you receive an AVR7000 receiver with the complaint “There is little or no output from the
subwoofer output jack, to drive my powered subwoofer”, follow the instructions below:
1) Check to make sure the AVR7000 is configured correctly for Subwoofer Output:
a) You will need a Video display (monitor or TV set, composite connection) connected to one of the
“Monitor Out” jacks at the rear of the AVR7000, to view the on-screen menu for these steps.
b) You will need a source, in this case a CD player, connected with RCA cables (Analog) to the CD input
jacks at the rear of the AVR7000. A Compact Disc with ample bass information should be inserted in
the CD player.
c) Connect a powered subwoofer to the Subwoofer Output Jack on the AVR7000.
d) With the AVR7000 turned ON, select input: Press the CD button on the remote control. The words
CD Player should appear in the display panel, as well as being indicated in the front panel Input
Indicators, by the green LED next to “CD” on the right-hand side of the panel.
e) Select Dolby Pro Logic: Press the OSD button on the remote control to bring up the AUDIO SET UP
menu. Press the
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button until the cursor is next to the SURROUND SETUP menu. Press the Set
button so that the SURROUND SETUP menu is on-screen. Since the factory default for all inputs is
Stereo, the words SURR OFF should initially appear. To change, press the
4
buttons until DOLBY
PRO LOGIC appears. A green LED will also light next to the DOLBY PRO LOGIC in the Surround
Mode Indicators on the left side of the front panel.
f) Press the
6
button until the cursor is next to RETURN TO MENU; press the Set button. You should
be back to the AUDIO SET UP menu. Move the cursor with the
6
button until it’s on the SPEAKER
SETUP line, then press the Set button to bring up the SPEAKER SETUP menu. For the first three
lines on the menu, the word SMALL should appear on the right side. If the word LARGE appears in
any of the lines, press the
6
button on the remote until it’s next to any line you need to change, and
then press the
4
button until SMALL appears. (When SMALL is selected, low frequency sounds will
be sent only to the subwoofer output.)
g) Make sure for the line SUBWOOFER, the word YES appears. If NO is there, press the
6
button on
the remote until it’s next to the SUBWOOFER line; press the
4
button until the word YES appears.
h) Press the OSD button on the remote control again, if desired, to turn off the On-Screen Display.
i) Turn on the CD player and play the CD, with the AVR7000 volume at a reasonable level, with the
powered subwoofer turned ON, with its volume control also turned up to a reasonable level. Has this
solved the problem ? If NO, proceed to step #2.
2) Check for sufficient solder on pin 5 of IC121. IC121 is an Op Amp (NJM5532M) on the DSP PCB.
CAUTION: THE AVR7000 CIRCUITS ARE ELECTROSTATICALLY SENSITIVE.
TO PREVENT DAMAGE TO THE RECEIVER, FOLLOW PROPER STATIC CONTROL PROCEDURES.
a) Remove the top cover, (16 Black Phillips screws). You should be working at the rear of the receiver.
b) Unplug the white ribbon cable from the rear of the DSP PCB (see figure 1)
c) Remove (13) black screws from the rear of the AVR7000 holding the Video and DSP PCB’s (see figure
2).
d) On the top of the Video PCB, remove the (3) remaining screws (2 black and 1 plated) holding the Video
PCB to the chassis; remove the single black screw holding the bracket support to the DSP PCB.
e) Unplug the small, white, 2-pin molex connector snaking across the top of the Video PCB.
f) Loosen (do not remove) the 2 remaining bracket support screws at the bottom of the bracket, at the
bottom of the AVR7000 chassis; you should now be able to push the bracket back far enough to be able
to remove both the Video and DSP PCB’s when necessary.
AVR7000 harman/kardon
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