Sony MZ-R900 Service Manual - Page 17

SECTION 5 ELECTRICAL ADJUSTMENTS MZ-R900 Outline • In this set, automatic adjustment of CD and MO can be per- formed by entering the test mode (see page 12). However, before starting automatic adjustment, the memory clear, power supply adjustment, and laser power check must be performed in the manual mode. • A key having no particular description in the text, indicates a set key. • For the LCD display, the LCD on the remote commander is shown, but the contents of LCD display on the set are same. Precautions for Adjustment 1. Adjustment must be done in the test mode only. After adjusting, release the test mode. 2. Use the following tools and measuring instruments. • Test CD disc TDYS-1 (Part No. : 4-963-646-01) • SONY MO disc available on the market • Digital voltmeter • Laser power meter LPM-8001 (Part No. : J-2501-046-A) • Thermometer (using the Temperature Correction) 3. Unless specified otherwise, supply DC 3V from the DC IN 3V jack (J601). 4. Switch position SYNCHRO REC switch OFF HOLD switch OFF Adjustment Sequence 1. NV Reset (Memory clear)   Manual Mode r  2. Power Supply Manual Adjustment  r  Overall Mode  3. Temperature Correction (item number: 014) r  4. Laser Power Check  Manual Mode  r  5. Electrical offset Adjustment  Caution: This adjustment must be made with  no disc loaded.   r  Overall Mode 6. CD Overall Adjustment   r  7. MO Overall Adjustment  r 8. RESUME Clear   Manual Mode  NV Reset Caution: On the set having the microcomputer version 1.000, some adjusted values were set in the manual mode at the shipment, but these data will be cleared when the NV is reset. Therefore, on the set having the microcomputer version 1.000, change the adjusted values following the Change of Adjusted Values immediately after the NV was reset. • Setting method of NV reset 1. Select the manual mode of the test mode, and set item number 021NV Reset (see page 13). Remote commander LCD display 021 ResNV CC 2. Press the X key. Remote Commander LCD display 021 ResOK? 3. Press the X key once more. Remote commander LCD display 021 Res*** NV reset (after several seconds) 021 Reset! 4. Press the x key to quit the manual mode, and activate the test mode (display check mode). • Change of Adjusted Values On the set having the microcomputer version 1.000, some adjusted values were set in the manual mode at the shipment, but these data will be cleared when the NV is reset. Therefore, on the set having the microcomputer version 1.000, modify the adjusted values through the following procedure immediately after the NV was reset. 1. Item numbers in which the adjusted values are to be modified Item number 832 Item number 862 Item number 871 Item number 872 2. Adjusted values modifying procedure 1) Select the manual mode of the test mode, and set item number 832 (see page 13). Remote commander LCD display 832 Pw-T W ** **:Adjusted value 2) Adjust with the [VOL+] key (adjusted value up) or [VOL--] key (adjusted value down) so that the adjusted value becomes E4. 3) Press the X key to write the adjusted value. 4) Select the manual mode of the test mode, and set item number 862 (see page 13). Remote commander LCD display 862 V1dat ** **:Adjusted value 5) Adjust with the [VOL+] key (adjusted value up) or [VOL--] key (adjusted value down) so that the adjusted value becomes 01. 6) Press the X key to write the adjusted value. 17