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ADJUSTMENT
PROCEDURE
for DEF &
POWER BOARD
The INPUT signal is to be the COLOR BAR
unless otherwise specified.
(1) Items Checked
i) Attach the DEF & POWER BOARD to the main
body of the monitor.
At this time, make sure that
the POWER switch of the monitor is turned off.
ii) Connect the specified cables to the connectors on
the PC board respectively.
Especially connect the
connectors of high voltage system securely.
(See below)
CRT anode cap
FOCUS connector
SCR connector
Deflection york connector
iii) Connector for switching the power supply input
Switching the power, 100V / 200V system of the
DEF & POWER
BOARD
is performed by
inserting the short connector into CN105 and
CN106.
Insert the connectors according to the supply
voltage, refering to the following table.
(2) Operation
Table 3
Insert short
connector
Open
Open
Insert short
connector
i) Set VR201 as well as SCR VR(which is close to
the components side of the PC board) of the
flyback transformer to MIN position and also set
other VRs all to each center position ..
ii) After connecting the signal cable, connect the AC
cable and then turn the POWER switch on.
iii) Make sure that no troubles are found after turning
the power on. Then, rotate slowly the SCR VR
clockwise to fet pictures shine on the screen and
set the SCR VR to the point where the luminance
of the pictures does not vary even when the SCR
VR is rotated.
iv) Inputting the signal of detailed figures, adjust the
FOCUS VR on the flyback transformer (above the
SCR VR) so that the pictures can be clear. Next,
adjust VR202 (NOR WIDTH),
VR204 (PIN
LEVEL), VR206 (SIDE PIN PHASE), VR207(H
CENT) and VR209 (V CENT) briefly. (Refer to
Table 4 of Scanning Size.)
Table 4
SCANNING SIZE
(3) Adjustment for Preventation of X-rays Radia-
tion
(D VR201 (PROTECT)
i) After checking that the POWER switch is
turned off, connect the high voltage meter to the
anode of CRT and also connect GND of the
hjgh voltage meter to that of CRT ..
ii) After turning on the POWER switch, adjust the
high voltage output to 28kV with VRlOl(+B
ADJ.).
iii) Rotating slowly VR201, set the VR to the point
where protection of the high voltage operates ..
iv) Tum the POWER switch off once after the
protection operates, adjust VRlOl so that the
high voltage output can be a little reduced.
Then, tum the POWER switch on again ..
v) Raise the high voltage output again with VRlOl
and check that the protection operates at 28kV.
vi) When the voltage for actuating the protection is
not 28kV, repeat the procedure of step iii) to vi).
@
VRlOl (+B
ADJ.)
i) Connect the "+" lead of a digital voltmeter to
TP102 and the " - " lead to
TP104 or the
chassis.
ii) Adjust VR101 so that the voltmeter can show a
reading of +ll0V.
iii) Check the following voltage at each TP.
TPlOl -+ 150V
±
2V
TP103 -+
45V
±
2V
TP105 -+
16V
±
2V
@ After having completed the above adjustments,
seal the whole adjusting side of VR101 and
VR201 using Cemedine No. 1500 (Araldite) as
shown in Fig.2.
These controls are not for field servicing and
are fixed with glue after setting to avoid X-ray
radiation which may cause one component
failure in the circuit and misadjustment of these
-
11 -
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