4) Adjustments Of Deflection System - Ikegami TM14-17R Service Manual

(4) Adjustments of Deflection System
The NTSC signal to VIDEO A input terminal or the
PAL signal to VIDEO B input terminal should be
inputted before the adjustments ..
CD
VR901 (H HOLD)
i) Select VIDEO A and connect the electrolytic
capacitor which is equivalent to 47
µ
F/25V
between TP901 and TP903(GND) to get a
horizontal free-running state.
ii) Adjust VRQ_0l(H HOLD) so that the pictures
can roll, slanting to the right.
@ VR902 (N. V HOLD)
i) Select VIDEO A and connect the electrolytic
capacitor which is equivalent to 47 µ F/25V
between TP902 and TP903(GND) to get a
vertical free- running state.
ii) Adjust VR902(N. V HOLD) so that the pictures
can roll upward a little faster.
@ VR401 (P .. V HOLD)
i) Select VIDEO B and connect the electrolytic
capacitor which is equivalent to 47 µF/25V
between TP9b2 and TP903(GND) to get a
vertical free- running state.
ii) Adjust VR401(P. V HOLD) so that the pictures
can roll upward a little faster.
@ VR903 (V BIAS)
i) Select VIDEO A and set the SCAN switch to
"NOR" position.
ii) Connect the probe to R248 (collector side of
Tr215) on the DEF & POWER BOARD and
adjust the voltage at the medium point of 1 V to
22V to 23V, half of the supply voltage ..
r-::::::::::::=i......,---1--==:::::::,,__,-_ 22Vto23V
1/2V 1/2V
----GND
iii) At this time, adjust generally HEIGHT(VR905),
LINEARITY(VR904), WIDTH (VR202 on the
DEF
&
POWER BOARD) and V CENT
(VR209 on the DEF & POWER BOARD),
refering to Scanning Size(Table 2)..
iv) Next, readjust VR903 so that the voltage at the
end of the V deflection can be +5V de ..
- 6 -
@ VR908 (H. PHASE)
i) Input the COLOR BAR and set the SCAN
switch on the FRONT PANEL to UNDER
SCAN position. Then, adjust VR908 so that the
picture can be positioned at the center of the
raster.(See Fig.1)
V
Raster
"
I"--
Picture
Fig .. 1
ii) Input the CROSS HATCH signal and check the
side pin. When the side pin is wrong, optimize
it with VR204(PIN LEVEL) and VR206(SIDE
PIN PHASE) on the DEF & POWER BOARD.
@
VR905(NOR HEI.)
VR904(V. LIN.)
VR209 (V CENT)
VR207(H CENT)
VR202 (NOR WIDTH)
} on the VIDEO BOARD
}
on
the
DEF &
POWER BOARD
Adjust the scanning size and V linearity in
normal scanning using the above VRs. (For the
scanning size, refer to Table 2 . .)
(J) VR906(U HEI.)
VR907(16:9 HEI)
VR203(US WIDTH)
} on the VIDEO BOARD
}
on the DEF
&
POWER BOARD
Using the above VRs, adjust the scanning sizes
of the pictures in under scanning as well as in
16:9 aspect ratio scanning as shown in the
following table.
Table 2 SCANNING SIZE
(5) Adjustments of VIDEO System-Level
Adjustment of LUMINANCE Signal
CD
VR601 (R GAIN)
i) Select AUX and set Sl(RGB/YPBPR selector
switch) on the VIDEO BOARD to "RGB"
position.