Harman kardon dvd 48 service manual
This is the 174 pages manual for harman kardon dvd 48 service manual.
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Extracted text from harman kardon dvd 48 service manual (Ocr-read)
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1 SERVICING PRECAUTIONS NOTES REGARDING HANDLING OF THE PICK-UP 1. Notes for transport and storage 1) The pick-up should always be left in its conductive bag until immediatel\ y prior to use. 2) The pick-up should never be subjected to external pressure or impact. 2. Repair notes 1) The pick-up incorporates a strong magnet, and so should never be brought\ close to magnetic materials. 2) The pick-up should always be handled correctly and carefully, taking care to avoid external pressure and impact. If it is subjected to strong pressure or impact, the result may \ be an operational malfunction and/or damage to the printed-circuit board. 3) Each and every pick-up is already individually adjusted to a high degree\ of precision, and for that reason the adjustment point and installation screws should absolutely never be touched. 4) Laser beams may damage the eyes! Absolutely never permit laser beams to enter the eyes! Also NEVER switch ON the power to the laser output part (lens, etc.) o\ f the pick-up if it is damaged. 5) Cleaning the lens surface If there is dust on the lens surface, the dust should be cleaned away by\ using an air bush (such as used for camera lens). The lens is held by a delicate spring. When cleaning the lens surface, t\ herefore, a cot- ton swab should be used, taking care not to distort this. 6) Never attempt to disassemble the pick-up. Spring by excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab. (Do not use any other liquid cleaners, because they will damage the lens.) \ Take care not to use too much of this alcohol on the swab, and do not allow the alcohol to get inside the\ pick-up. Storage in conductive bag NEVER look directly at the laser beam, and donÕt let contact fingers or other exposed skin. Magnet How to hold the pick-up Conductive Sheet Cotton swab Pressure Pressure Drop impact 2
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2 NOTES REGARDING COMPACT DISC PLAYER REPAIRS 1. Preparations 1) Compact disc players incorporate a great many ICs as well as the pick-up\ (laser diode). These compo- nents are sensitive to, and easily af fected by, static electricity . If such static electricity is high voltage, components can be damaged, and for that reason components should be hand\ led with care. 2) The pick-up is composed of many optical components and other high-precis\ ion components. Care must be taken, therefore, to avoid repair or storage where the temperature of\ humidity is high, where strong magnetism is present, or where there is excessive dust. 2. Notes for repair 1) Before replacing a component part, first disconnect the power supply\ lead wire from the unit 2) All equipment, measuring instruments and tools must be grounded. 3) The workbench should be covered with a conductive sheet and grounded. When removing the laser pick-up from its conductive bag, do not place th\ e pick-up on the bag. (This is because there is the possibility of damage by static electricity .) 4) To prevent AC leakage, the metal part of the soldering iron should be grounded. 5) W orkers should be grounded by an armband (1M Ω) 6) Care should be taken not to permit the laser pick-up to come in contact \ with clothing, in order to prevent static electricity changes in the clothing to escape from the armband. 7) The laser beam from the pick-up should NEVER be directly facing the eyes\ or bare skin. Resistor (1 Mohm) Conductive Sheet Resistor (1 Mohm) Armband DVD48 harm an /k ar don 3