Philips L04LAA Service Manual page 5

Safety and Maintenance Instructions, Warnings, and Notes
•
The picture tube panel has printed spark gaps. Each spark
gap is connected between an electrode of the picture tube
and the Aquadag coating.
•
The semiconductors indicated in the circuit diagram and in
the parts lists, are interchangeable per position with the
semiconductors in the unit, irrespective of the type
indication on these semiconductors.
2.4.2
Schematic Notes
•
All resistor values are in ohms and the value multiplier is
often used to indicate the decimal point location (e.g. 2K2
indicates 2.2 kohm).
•
Resistor values with no multiplier may be indicated with
either an "E" or an "R" (e.g. 220E or 220R indicates 220
ohm).
•
All capacitor values are expressed in:
micro-farads (µ= x 10^-6),
nano-farads (n= x 10^-9), or
pico-farads (p= x 10^-12).
•
Capacitor values may also use the value multiplier as the
decimal point indication (e.g. 2p2 indicates 2.2 pF).
•
An "asterisk" (*) indicates component usage varies. Refer
to the diversity tables for the correct values.
•
The correct component values are listed in the Electrical
Replacement Parts List. Therefore, always check this list
when there is any doubt.
2.4.3
Practical Service Precautions
•
It makes sense to avoid exposure to electrical shock.
While some sources are expected to have a possible
dangerous impact, others of quite high potential are of
limited current and are sometimes held in less regard.
•
Always respect voltages. While some may not be
dangerous in themselves, they can cause unexpected
reactions - reactions that are best avoided. Before reaching
into a powered TV set, it is best to test the high voltage
insulation. It is easy to do, and is a good service precaution.
•
Before powering up the TV set with the back cover off
(or on a test fixture), attach a clip lead to the CRT DAG
ground and to a screwdriver blade that has a well insulated
handle. After the TV is powered "on" and high voltage has
developed, probe the anode lead with the blade, starting at
the case of the High Voltage Transformer (flyback - IFT).
Move the blade to within two inches of the connector of the
CRT.
If there is an arc, you found it the easy way, without
getting a shock! If there is an arc to the screwdriver blade,
replace the part that is causing the problem: the High
Voltage Transformer or the lead (if it is removable).
2.4.4
Lead Free Solder
This set is manufactured with lead-free production technology.
This is also indicated on the PWB by the PHILIPS lead-free
logo (either by a service-printing or by a sticker).
Figure 2-2 Lead-free logo
This set is produced with lead-free solder alloy as well as with
lead-free sub-parts. It can be considered as lead-free.
Due to this fact, some rules have to be respected by the
workshop during a repair:
•
Use only lead-free soldering tin Philips SAC305 with order
code 0622 149 00106. If lead-free solder paste is required,
please contact the manufacturer of your soldering
equipment.
P
b
L04L AA
•
Use only adequate solder tools applicable for lead-free
soldering tin.
•
Adjust your solder tool so that a temperature around
217 - 220 deg. C is reached at the solder joint.
•
Do not mix lead-free soldering tin with leaded soldering tin;
this will lead to unreliable solder joints!
•
Use only original spare parts listed in this manual. These
are lead-free parts!
•
On the website www.atyourservice.ce.philips.com you can
find more information on:
–
Aspects of lead-free technology.
–
BGA (de-)soldering, heating-profiles of BGAs used in
Philips sets, and others
2. EN 5