Denon DCD-1500II Service Manual

eeeeeeeaCautions for Handling the Laser Pick-upThe laser pick-up KSS-151A is assembled and preciselyadjusted using a sophisticated manufacturing process in ourplant. Do not disassemble or attempt to readjust it. Pleasekeep the following instructions carefully in handling pick-up.1. General Care(1) StorageDo not store the pick-up in dusty, high-temperaturedor high-humidity environments.(2) Please take care for preventing from shock by fallingdown or careless handling.2. Laser Diode (LD)(1) Protect your eyesThe laser beam may damage the human eye, since theintensity of the focused spot may reach 1.3 x 10* W/cm? even if the intensity at the object lens is 400 UWmaximum, As the light beam spreads after focusedthrough the objective lens, it does not effect you in theplace as far as more than 30cms. However, do notlook at the laser light beam either through theobjective lens directly nor another lens or a mirror,(2) Poison of AsSince the LD chip contains As (Arsenic), as GaAs +GaAlAs, as known as the poison, although the poisonis relatively weak, in comparing. with others, e.g.As,03, AsCl3 etc., and the amount is small, avoidputting the chip in acid or an alkali solution, heating itover 200°C or putting it into your mouth... ..(3) Avoid surge current or electrostatic dischargeThe LD may be damaged or deteriorated by it’s ownstrong light if a large current is supplied to it, even ifonly a short pulse. —-Make sure that there is no surge current in the LDdriving circuit by switches or else. Be careful to handlepick-up as it may be damaged in a moment by humanelectrostaic discharge. The pins of the LD are short-circuited by solder for protection during shipment(Soldered short circuit portion (A)].For safety handling of an LD, grounding the humanbody, measuring equipments and jig is strongly recom-mended, And still it is further desirable to make use ofmat on the platform and floor for handling the LD.To open the short circuit, remove the soldering quicklywith a soldering iron whose metal part is grounded.The temperature of the soldering iron should be lessthan 320°C (30W).'\ 3, X-axis Actuator(1) The performance of the actuator may be effected ifmagnetic material is located nearby, since the actuatorhas a strong magnetic circuit. Do not permit dust toenter through the clearance of the cover.(2) Cleaning the lensIt may change the specifications when dust or dirt isstuck on the object lens.For cleaning, use a dry_tense¥@aning paper applyingno excessive pressure to the lens. If it is difficult to re-move it, moisten the paper with a little amount ofwater. At this time never drip water other than the lensportion.4. The Metal BearingThe metal bearing of Cu-compound sintered alloy is im-pregnated with oil. However, supply oi! with the specifiedoil Froil 0147P, at the pick-up replacing time. You do notnormally need lublicate the bushing in initializing time norsupplying oil in running time.5. HandlingPlease handle the laser pick-up with holding by opticalbase.When either a part of human body or some other thingsmay happen to touch directly with the circuit part of eitherthe LD or PD PCB, it may cause deterioration, take carefulattention in handling this base.6. Deterioration of Laser Pick-upWhen difficulty occurs either in focus or tracking adjust-ment nor able to adjust the focus or tracking, it seems thatthe laser pick-up is deteriorated. In these cases, check avalue of laser diode current and give a decision fordeterioration.7. Fundamental Deterioration Decision of Laser Pick-up(1) If a voltage value across Pin @) of TP102 (+5V) andPin @ (iop) of Unit (2U-1454) is V1, the value of laserdiode current “‘iop 1’’ can be found a formulaiop it(2) If a “iop” exceeds +10% compared with the IOP indi-cation on the laser pick-up mameplate, there is a fairchance for deterioration when it is checked under acircumambient temperature 23°C.(3) When the circumambient temperature changes +10°C,“iop 1” will change 5%. The “‘iop 1°’ will also bechanged the passage of time.(4) In case of the above conditions taking into considera-tion and performed the adjustment in proper way, ifthe HF level across pin (1) and across (HF) GND ofTP102 in 2U-1454 becomes 0.6V or less values; or a _gitter occurs great, the laser pick-up is may bedeteriorated.