Philips MX975D, Service Manual

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Power Supply-This receiver is designed for operation on 120 Volts, 6OHz alternating current (ac) only.
Never connect to a supply having a different frequency or voltage.
IMPORTANT NOTICE
This device employs many circuits, components, and mechanical parts designed for protection against
fire, shock and RF interference. For continued safety any servicing should be performed by qualified
personnel and exact replacement parts should be used. Under no circumstances should the original
design be altered.
PRODUCT SAFETY GUIDELINES FOR ALL PRODUCTS
CAUTION
: Do not modify any circuit. Service work should be performed only after you are thoroughly
familiar with all of the following safety checks. Risk of potential hazards and injury to the user increases
if safety checks are not adhered to.
USE A SEPARATE ISOLATION TRANSFORMER FOR THIS UNIT WHEN SERVICING.
PREVENTION OF ELECTROSTATIC DISCHARGE (ESD)
Some semiconductor solid state devices can be damaged easily by static electricity. Such components
commonly are called Electrostatically Sensitive (ES) Devices, Examples of typical ES devices are
integrated circuits and some field-effect transistors and semiconductor "chip" components. The following
techniques should be used to help reduce the incidence of component damage caused by electrostatic
discharge (ESD).
1. Immediately before handling any semiconductor component or semiconductor-equipped assembly,
drain off any ESD on your body by touching a known earth ground. Alternatively, obtain and wear a
commercially available discharging ESD wrist strap, which should be removed for potential shock reasons
prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive
surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static solder removal device. Some solder removal devices not classified as "antistatic
(ESD protected)" can generate an electrical charge sufficient to damage ES devices.
5. Do not use freon·propelled chemicals. These can generate electrical charges sufficient to damage ES
devices.
6. Do not remove a replacement ES device from its protective package until immediately before you are
ready to install it (Most replacement ES devices are packaged with leads electrically shorted together by
conductive foam, aluminum foil or comparable conductive material).