Safety Related Adjustment; Equipment Required; Hold-Down Confirmation And Readjustment - Sony SSM-175A Service Manual

3-1. Equipment Required

. Pattern generator
. DC power supply
3-2. Hold-Down Confirmation and
Readjustment
( R406: A Board)
Note : The following adjustment should always be performed when
replacing the following components (marked with
diagram).
: L901 (DY)
R406, R408, C415, C410, C414, D405 (A board)
1. Receive monoscope signal.
2. Set controls and switch as follows.
CONTRAST control ............... minimum
BRIGHT control ..................... minimum
3. Apply an external DC voltage gradually to cathode of
D404, and when the voltage becomes 21 V DC,
confirm HOLD DOWN circuit operates immediately
and raster disappears.
4. When the voltage becomes 17 V DC, confirm HOLD
DOWN circuit does not operate.
5. If step 3 and 4 are not satisfied, replace R406 and
repeat above steps.
SSM-175A/175ACE
Section 3

Safety Related Adjustment

on the schematic
A Board (A side)
T402
D404
R406
Regulated-DC
power supply
3-1