Tait TM8100 mobiles, Service Manual

Page: 121 / 620

TM8100/TM8200 Service Manual General Information 121
© Tait Electronics Limited November 2007
Spare Cans
It is good practice to discard any can that has been removed and replace it
with a spare can. If this is not done, special precautions are needed when re-
installing the original can. These precautions are discussed as part of the
training for accreditation.
4.7 SMT Repair Techniques
Standard
Procedures
Service centres carrying out level-2 repairs are expected to be familiar with
the standard techniques for the replacement of SMT components. However,
certain components on the main board require non-standard techniques and
these are discussed below. Another issue of concern is the procedure for
removing and installing cans. A discussion of the issue concludes this section.
Non-standard
Procedures
Do not use the standard SMT repair techniques when replacing the
capacitors C548 and C565 and the inductors L601 and L602. The standard
techniques tend to produce excessive heat, which will damage these
components. Do not use a hot-air tool or heat gun. Instead use solder paste
and a standard soldering iron with an iron tip with a specified temperature
of 600°F (315°C). The capacitors are part of the frequency-synthesizer
circuitry under the
SYN TOP
can. The inductors are part of the SMPS of the
power-supply circuitry on the bottom-side of the board. Figure 4.5 on
page 122 shows the locations of the components.