Siera CTS-AA, Руководство по обслуживанию

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8.5.3 White checking:
- Connect pattern generator containing grey scale
- Adjust the set to normal operation and reduce the saturation control to minimum.
- Allow the set to warm up about 10 minutes and check visually if the grey scale has correct colour.
- If not, enter to Service menu and adjust G and B gain (items 14 and 15) until a desired grey is obtained. In the case
that adjusting is difficult, start again with the setting values of table 8.1 (items 9, 10, 13, 14, 15).
8.6 Geometry
- Connect a circle pattern generator with the controls at nominal conditions and enter to service menu.
- Horizontal shift:
Adjust to have picture centred in horizontal position by service menu item 18.
- Vertical amplitude:
Adjust picture height to cover the screen by service menu item 19.
- Vertical centring:
Occasionally it is possible to correct the vertical centring cutting resistors R3400 or R3401
- TXT Shift:
Horizontal shift of OSD or TXT can be adjusted by item 20 of service menu.
8.7 Options:
The type of chassis is defined by items 21 and 22 of service menu. The following alternatives are available:
Important note: All the chassis have identification sheet when the chassis type is indicated:
«Cod. service: SXXMXX», where SXX means the option of system and MXX means the option of menu
Example: S03M00 means system = 03 (Pal-Secam B/G-DK) and menu = 00 (13 Languages menu)
When the chassis or the EEPROM (IC7685) have to be replaced, be careful to keep the same type of chassis,
setting correctly the chassis options.
8.8 Error messages
The microcomputer also detects errors in circuits connected to the I2C (Inter IC) bus. These error messages are
communicated via OSD (On Screen Display) :