.
SAFETY PRECAUTIONS
An isolation transformer should be connected in the power line between the receiverand the AC line beforeany
sewice is performed on the receiver.
INSTALLATION AND SERVICE ADJUSTMENTS
X-RADIATION PRECAUTION The primary source of X-RADIATION,in television receiver is the picture tube. The picture tube ia ~
cially constructed to limit X-RADIATION emissions. For continued X-RADIATION protection, the replacement tube must be the
same type as the original
including suffix letter. Excessive high voltage mav Produce potentially hazardous X-RADIATION. To
avoid such hazards, the high voltage must be
maintained within specified limit: Refer to this eewice manual, high v@tage for
specific high voltage limits.
If high voltage exceeds SpeCifkd limits, take necessary corrective action. carefully fOllOWthe inet~c.
tions for + B1 volt power supply adjustment, and high voltage check to maintain the high voltage within the specified limits.
AGC AMJSTMENT
NOTE: Do not attempt this adjustment
with weak signal.
,
1.
:
2.
3.
v
Tune receiver to most clearest (or strongest) VHF station in
your area.
Set brightness and contrast controls to maximum.
Set colour control to minimum.
Set the
AGC (VR101) control to mid-range.
Turn AGC control in direction which causes snow to appear,
then in the opposite direction until the snow just disappears.
SUB BRIGHTNESS AWUSTMENT
1.Connect a DC meter between “TP-H” (positive lead) and
“TP-G” (negative lead) on main unit.
2. Receive the circular pattern.
3. Set brightness to maximum and contrast to minimum,
4. Adjust sub brightness control (VR211) for 0.3V
N~E: If picture tube replace.
Check Sub-brightness ad-
justment.
VERTICAL SIZE AilWSTMENT
1. Tune the receiver to mono-chrome circular pattern.
2. Adjust vertical size (VR451) control
for full scan.
HORIZONTAL CENTER A~USTMENT
1.
2.
3.
L
B1
Tune the receiver to mono-chrome circular pattern.
Set the brightness and contrast to maximum.
Adjust Video Phase (VR411) for optimum horiz center position.
POWER SUPPLY AIXH.JSTMENT
1. Connect DC meter to “TP-B” and ground.
Set the + B1 adjustment control (VR311) to mid-range.
2. Set brightness and contrast to minimum.
i
Tune the receiver to an active channel and synchronize picture.
3. Adjust + B1 adjustment control for 131~1.O volt DC.
TUNING DISPLAY WIDTH AWJSTMENT
1. Tune the receiver to mono-chrome circular pattern.
2. Set the mode switch (SW331 C) to on.
Tuning bar is displayed on screen.
3. Adjust VR 750 on the
V/S UNIT for optimum the tuning bar
width.
Set the mode switch to off.
VIDEO DET. AMJSTMENT
1.
2.
w
Tune receiver to colour bar pattern. (See Fig. 1)
Connect the oscillator to TP-F.
Adjust VR121 for 1.0f 0.05Vp-p (Video det. waveform),
GREY SCALE AND TRACKING AWUSTMENT
Tune the receiver to mono-chrome pattern.
1.
2
3.
4.
5.
6
7.
8
Set the brightness and the contrast to maximum,the colour
to normal.
Connect the service tip to KSV-2 (service condition).
Set screen control to minimum. (fully counter-clockwise).
Turn screen control to obtain just visible one coloumd line.
Adjust each bias (VR621-Green, VR601-Blue, VR611-Red)
controls alternately until a dim white line produced.
Re-connect the service tlp to KSV-l (normal condition).
Adjust red (VR612) and blue (VR602) drive controls alternate
Iy to
produce normal black and white picture.
Check for proper grey scale tracking at all brightness Iewk.
NOTE If grey scale adjustment IS made after picture tube
replacement, check high voltage and
subbrightnees
adjustments.
COLOUR A~USTMENT (PAL)
Receive colour bar pattern. (See Fig. 1)
Set’s controls: brightness . . . . . . . maximum
colour . . . . . . . . . .. maximum
contrast . . . . . . . . . mid-range
\ ADJUST I
REMARKS
Connect the oscilloscope to TP6B on CRT unit.
Adjust VR251, T281 to obtain each lH
r
1 VR251 , T281
I
—
2
T211
waveform (amplitude) for same as shown
below.
&ll-1+-lH+
~...
““n
u
B-Y WAVE;ORM
Figure 2
Adjust T211 to obtain proper waveform a:
shown in Figure 2.
FOCUS ACAJUSTMENT
Adjust focus control on the right side of the chassis for well
scanning lines.
HIGH VOLTAGE CHECK
1.Tune the receiver to the circular pattern.
2. Set brightness and contrast to maximum.
3. Connect a high voltage probe to anode lead at picture tube.
4. High voltage must measure between 26- 28KV.
NOTE: If picture tube replace, check high voltage.
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