Technics SJ-HD501, Servise Manual

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Cautions
1. About handling the MD unit
- The magnetic head is a precision unit and is very fragile. Do not deform it.
- Laser diode in the optical pickup may be destroyed by the staticelectricity
generated in your clothes or body. Be especially careful with the static
electricity.
- The optical pickup is structured extremely precisely. Do not subject to the
strong impact or shock. Do not touch the lens.
2. About handling the magnetic head
When replacing the magnetic head, do not tighten the mounting screw (RHD17022)
too firmly. If the screw is tightened too much to deform the resin, the position of
the head is moved, and this affects its recording operation.
Recommended torque for mounting screw: 700 g cm +/- 100 g cm
Reference: This is the same force as using a screwdriver with a 15-mm diameter
grip, you fasten the screw naturally with your thumb and index finger.
3. About the driver for adjusting laser power
Use only insulated driver such as a ceramic driver. With the metal driver, it is not
possible to adjust properly because of the induction noise. Also, if it short-circuits
with the chassis, it may destroy or damage the laser diode.
Recommended driver: VESSEL 9000 1.8 -30 (Ceramic driver)
Cautions on optical pickup:
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