Handling Precautions For Traverse Deck; Handling Of Traverse Deck (Optical Pickup); Grounding For Electrostatic Breakdown Prevention - Technics SL-HD301 Service Manual

SL-HD301 / SL-HD501
4 Handling Precautions for Traverse Deck
The laser diode in the traverse deck (optical pickup) may break
down due to potential difference caused by static electricity of
4.1.
1.Do not subject the traverse deck (optical pickup) to static
electricity as it is extremely sensitive to electrical shock.
2.The short land between the No. 5 (GND) and No. 4 (LD)
pins on the flexible board is shorted with a solder build-up
to prevent damage to the laser diode. (As shown in Fig. 1.)
To connect to the PC board, be sure to open by removing
the solder build-up, and finish the work quickly.
3. Take care not to apply excessive stress to the flexible board
(FFC).
4. Do not turn the variable resistor (laser power adjustment). It
has already been adjusted. (As shown in Fig. 1.)
4.2.
1. Human body grounding
Use the anti-static wrist strap to discharge the static
electricity from your body. (As shown in Fig. 2.)
2.Work table grounding
Put a conductive material (sheet) or steel sheet on the area
where the optical pickup is placed, and ground the sheet.
Caution:
The static electricity of your clothes will not be grounded
through the wrist strap. So, take care not to let your clothes
touch the traverse deck (optical pickup).
No.5 (LD GND) pin
clothes or human body.So, be careful of electrostatic
breakdown during repair of the traverse deck (optical pickup).
Handling of traverse deck (optical pickup)
Flexible board (FFC) Lens
(Handle it carefully)
(Do not touch)
Variable resistor
No. 4 (LD) pin (Do not turn)
Clip or short-pin
Fig. 1
Grounding for electrostatic breakdown prevention
Wrist strap
(Anti-static bracelet)
plate or some metals
to conduct electricity