First issue 10 / 04
5
3. Design Alteration Warning: Do not alter or add to the mechanical or electrical design of this unit. Design alterations and
additions, including, but not limited to, circuit modifications and the addition of the items such as auxiliary audio and/or
video output connections might alter the safety characteristics of this Projection Monitor and create a hazard to the user.
Any design alterations or additions will void the manufacturer's warranty and will make you, the service, responsible for
personal injury or property damage resulting therefrom.
4. Hot Chassis Warning:
a. Some Monitor chassis are electrically connected directly to one conductor of the AC power cord and may be safely
serviced without an isolation transformer only if the AC power plug is inserted so that the chassis is connected to the
ground side of the AC power source. To confirm that the AC power plug is inserted correctly, with an AC voltmeter
measure between the chassis and a known earth ground. If a voltage reading in excess of 1.0V is obtained, remove
and reinsert the AC power plug in opposite polarity and again measure the voltage potential between the chassis
and a known earth ground.
b. Some Monitor chassis normally have 85V AC (RMS.), between chassis and earth ground regardless of the AC plug
polarity. These chassis can be safely serviced only with an isolation transformer inserted in the power line between
the receiver and the AC power source, for both personnel and test equipment protection.
c. Some Projection Monitor chassis have a secondary ground system in addition to the main chassis ground. This
secondary ground system is not isolated from the AC power line. Insulating material that must not be defeated or
altered electrically separates the two ground systems.
5. Observe original lead dress. Take extra care to assure correct lead dress in the following areas:
a. near sharp edges,
b. near thermally hot parts (be sure that leads and components do not touch thermally hot parts),
c. the AC supply,
d. high voltage,
e. antenna wiring. Always inspect in all areas for pinched, out-of-place, or frayed wiring. Do not change spacing
between components and between components and the printed-circuit board. Check AC powers cord for damage.
6. Components, parts, and/or wiring that appear to have overheated or are otherwise damaged should be replaced with
components, parts, or wiring that meet original specifications. Additionally, determine the cause of overheating and/or
damage and, if necessary, take corrective action to remove any potential safety hazard.
7. PRODUCT SAFETY NOTICE: Many Monitor electrical and mechanical parts have special safety-related characteristics
some of which are often not evident from visual inspection, nor can the protection they give necessarily be obtained by
replacing them with components rated for higher voltage, wattage, etc. Parts that have special safety characteristics are
identified in this service data by shading with a mark on schematics. Use of a substitute replacement part that does not
have the same safety characteristics as the recommended replacement part in this service data parts list might create
shock, fire, and/or other hazards.
