Sony MZ-R91 service manual Section Servicing Notes, Eeprom

SECTION 1

SERVICING NOTES

NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT

The laser diode in the optical pick-up block may suffer electro- static break-down because of the potential difference generated by the charged electrostatic load, etc. on clothing and the human body.

During repair, pay attention to electrostatic break-down and also use the procedure in the printed matter which is included in the repair parts.

The flexible board is easily damaged and should be handled with care.

NOTES ON LASER DIODE EMISSION CHECK

Never look into the laser diode emission from right above when checking it for adjustment. It is feared that you will lose your sight.

NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK (LCX-2R)

The laser diode in the optical pick-up block may suffer electro- static break-down easily. When handling it, perform soldering bridge to the laser-tap on the flexible board. Also perform mea- sures against electrostatic break-down sufficiently before the op- eration. The flexible board is easily damaged and should be handled with care.

laser-tap

•When repairing this device with the power on, if you remove the MAIN board or open the upper panel assy, this device stops working.

In this case, you can work without the device stopping by fas- tening the hook of the open/close detect switch (S801) with tape.

upper panel assy

tape

S801 MAIN board

•This set is designed to perform automatic adjustment for each adjustment and write its value to EEPROM. Therefore, when EEPROM (IC802) has been replaced in service, be sure to per- form automatic adjustment and write resultant values to the new

EEPROM.

(Refer to Section 5 Electrical Adjustment. (page 18))

•Replacement of CXD2660GA (IC502) and CXR701080-013GA (IC801) used in this set requires a special tool. Therefore, they cannot be replaced.

OPTICAL PICK-UP FLEXIBLE BOARD

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