HCD-V8800, LBT-V8800AV - Sony Audio Service Manual (repair manual). Page 5

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2-1.  Operating procedure of Aging Mode

1. Load a commercially available 10-minute tape into the decks

A and B respectively.
(If a 10-minute tape is not available, another tape may be
used but a cycle time will be longer.)

2. Select the function “TAPE”.
3. Rewind tapes in advance by pressing  

0  button respec-

tively on decks A and B.

4. Press three buttons  SPECTRUM ANALYZER  ,  ENTER  ,

and  KARAOKE PON/MPX  simultaneously.

5. Press  

·  button on deck A.  (This button triggers the aging

mode.)

6. The aging mode is activated if “AGING A” is displayed on

the fluorescent indicator tube.

7. In the aging mode, the aging is executed in a sequence given

in “2-2.  Operation during Aging Mode”.
The aging continues unless an alarm occurred.

8. To exit from the aging mode, press  POWER  button to turn

the set OFF.

2-2.  Operation during Aging Mode
In the aging mode, the program is executed in the following se-
quence.

1. A tape on FWD side is played for one minute.
2. PAUSE STOP is made.
3. Recording is made for 3 minutes. (For the deck not having

the record function, the play is executed.)

4. FF is executed up to the end of tape.
5. A tape is reversed, and the tape on REV side is played for

one minute.

6. PAUSE STOP is made.
7. Recording is made for 3 minutes.  (For the deck not having

the record function, the play is executed.)

8. FF is executed up to the end of tape.
9. Steps 1 through 8 are executed for the other deck.
10. Steps 1 through 9 are repeated unless an alarm occurred.

2-3.  Deck Selection Sequence

• During the aging mode, decks are selected in the following se-

quence:

Deck A (FWD) 

→

 Deck A (REV)

↑

↓

Deck B (REV) 

←

 Deck B (FWD)

This model has the self-diagnosis function for the VIDEO and
AUDIO decoder sections.
Immediately after the power on, the self-diagnosis function searches
each operation of IC’s around the mechanism control microcom-
puter (IC701).
The results can be checked by connecting an oscilloscope to TP709
(LED) of the VIDEO board.

Oscilloscope (Waveform)

Symptom

H

L

Light

H

L

1 time blinking

H

L

3 time blinking

No error

DRAM (IC251) error

H

L

2 time blinking

External SRAM (IC751)
error

MPEG decoder (IC201)
error

oscilloscope

VIDEO board
TP709 (LED)

+
–

Note: The LED for check (D701) is mounted to some sets

(FORMER TYPE). In this case, confirm the lighting condi-
tion of LED.

X901

TP709 (LED)

IC751

IC251

D701

IC771