XOCECO M2019, Service Manual

Page: 5 / 39

3
3) Connect the power plug to AC 220V/50Hz, turn on the power switch, wait for normal raster, Check B
+
=
110V±0.2V.
Test point B+ B1-5V B2-8V B3-10V B4-32V TH-12V TH-20V TH-200V
DC(V) 110 5 8 12 32 12 20(22) 200
INSTALLATION AND SERVICE ADJUSTMENTS
GENERAL
In the majority of cases, a color television receiver will need only slight touch – up adjustment upon
installation. Check the basic characteristics such as FS,EHV,and focus. Observe the picture for good black and
white details without objectionable color shading. If color shading is evident, demagnetize the receiver.
If color shading still persists, perform purity and convergence adjustments. This should be all that is necessary
to achieve optimum receiver perfomance.
FOCUS ADJUSTMENT
Adjust the FOCUS control (on T301) for well defined scanning lines on the picture screen.
HIGH VOLTAGE CHECK
CAUTION: These is no HIGH VOLTAGE ADJUSTMENT on this chassis. Checking should be done
following the steps below.
1. Connect an accurate high voltage meter to the second anode of the picture tube.
2. Turn on the receiver. Set the BRIGHTNESS and CONTRAST controls to minimum (zero beam current).
3. High voltage will be measured below 26.5(20”)KV.
4. Vary the BRIGHINESS control to both extremes to be sure the high voltage does not exceed the limit
under any conditions.
General instruction
1. This chassis’ EEPROM'(N801 M24C08) should copy standard data, if necessary, deal it with “factory
adjustment”. If directly use blank EEPROM, should first preset I
2
C data, then go on other common
alignment. For factory adjustment method, refer to The appendix: factory menu.
2. If without special indication, the alignment is conducted on the below condition:
a) AC power supply 220 V/50 Hz.
b) The whole unit is preheated for more than 30 min.
3. There is built-in auto degaussing circuit, it will degauss automatically within 1second after turning on.
4. If CRT is with magnetism and affects color purity and convergence, the internal degaussing can not degauss
completely, can use degaussor to degauss externally. If color purity and convergence is still poor, then
do color purity and convergence adjustment.
Alignment items and procedure
1. B+ voltage check
2. RF AGC voltage adjustment
3. Focus adjustment
4. Screen-grid voltage and white balance adjustment
5. Horizontal,vertical scan center adjustment
6. Horizontal,vertical scan amplitude adjustment
7. Pattern correction adjustment
8. The alignment flow chart see figure below.