Servicing Notes; Power Supply During Servicing; Jog And Leds Check Mode; Selection Of Input Signal - Sony MDS-EX77 Service Manual

1-1. POWER SUPPLY DURING SERVICING

This set has no power supply in it, and it does not operate indi-
vidually. Therefore, connect to the pre/main amplifier system (TA-
EX77) for the DHC-MD77 or DHC-EX77MD in servicing. If
TA-EX77 is not available, use the power feed jig (PFJ-1) and jig
(J-2501-078-A). Using the jig, press the power switch (S408) on
the MAIN board in this set to turn on the power.
Connection:
Power feed jig
(PFJ-1)
P707,909
CDP/TC
jig
(J-2501-078-A)
CN904 CN902
(17P) (7P)
connector cable (17P)
(attached to the PFJ-1)
Parts Location:
MAIN board (Component Side)
SECTION 1

SERVICING NOTES

CN501 (7P)
SYSTEM CONTROL connector
set
connector cable (7P)
(attached to the set)
(S408)
Power switch
1-2. FLUORESCENT INDICATOR TUBE/BUTTONS/
JOG&LEDs CHECK MODE
1. While pressing the CD SYNC + CONTINUE buttons simul-
taneously, insert the power cord of TA-EX77 (pre/main am-
plifier) into the power outlet, then release the buttons. (Thus,
the check mode is activated.)
2. When buttons are released, "Key Check" is displayed for a
moment, then fluorescent indicator tubes are all turned on.
(LED for ANALOG IN indication is also turned on.)
3. As the buttons other than CD SYNC are pressed, fluores-
cent indicator tubes, one block each, are turned off, and all
tubes are off when operation of all buttons (except CD SYNC
button) is finished. (ANALOG IN LED is turned off when p
button is pressed.)
4. Press the CD SYNC button with fluorescent indicator tube
in all off status, "Key TEST OK!" is displayed for a moment,
then "JOG&LEDCheck" is displayed. (At this time,
if REPEAT button is pressed, "STANDBY" is displayed and
blinking, implying that normal operation is ready.)
5. With "JOG&LEDCheck" displayed, turning the SELECTOR
konb, and all LEDs simultaneously turn on and off repeatedly.
(If REPEAT button is pressed, normal operation is ready.)
6. With "JOG&LEDCheck" displayed, press the CD SYNC button,
and "SegmentCheck" is displayed for a moment, then segment
display is made. (If REPEAT button is pressed, normal op-
eration is ready.)
7. Press the CD SYNC button, and "end" is displayed. Then,
press the REPEAT button to finish the check mode.

1-3. SELECTION OF INPUT SIGNAL

With the power turned on, turning the SELECTOR konb while
pressing the p button to select either of the following:
Analog in
Digital 1 in
Digital 2 in
– 4 –