Sony MZ-R90/R91 User Manual

– 4 –

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.

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

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

• 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.

• 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 page 20.)

• Replacement of CXD2660R (IC502) and CXR701081 (IC801)

used in this set requires a special tool. Therefore, they cannot be
replaced.