Section 6: Customer Service
6-3
Moseley SL9003Q
602-12016-01 Revision J
Field Repair Techniques
If an integrated circuit is suspect, carefully remove the original and install the new one,
observing polarity. Installing an IC backward may damage not only the component itself,
but the surrounding circuitry as well. ICs occasionally exhibit temperature-sensitive
characteristics. If a device operates intermittently, or appears to drift, rapidly cooling the
component with a cryogenic spray may aid in identifying the problem.
If a soldered component must be replaced, do the following:
•
Use a 40W maximum soldering iron with an 1/8-inch maximum tip. Do not use a
soldering gun. Excessive heat can damage components and the printed circuit. Surface
mount devices are especially heat sensitive, and require a lower power soldering iron. If
you are not experienced with surface mount components, we suggest that you do not
learn on critical equipment.
•
Remove the solder from the component leads and the printed circuit pads. Solder
wicking braid or a vacuum de-solderer is useful for this. Gently loosen the component
leads and extract the component from the board.
•
Form the leads of the replacement component to fit easily into the circuit board pattern.
•
Solder each lead of the component to the bottom side of the board, using a good brand
of rosin-core solder. We recommend not using water soluble flux, particularly in RF
portions of the circuit. The solder should flow through the hole and form a fillet on both
sides. Fillets should be smooth and shiny, but do not overheat the component trying to
obtain this result.
•
Trim the leads of the replacement component close to the solder on the pad side of the
printed circuit board with a pair of diagonal cutters.
•
Completely remove all residual flux with a cotton swab moistened with flux cleaner.
For long term quality, inspect each solder joint – top and bottom – under a magnifier and
rework solder joints to meet industry standards. Inspect the adjacent components soldered
by the Moseley Associates production line for an example of high reliability soldering.
Summary of Contents for Starlink SL9003Q
Page 86: ...5 22 Section 5 Module Configuration Moseley SL9003Q 602 12016 01 Revision J ...
Page 90: ...6 4 Section 6 Customer Service Moseley SL9003Q 602 12016 01 Revision J ...
Page 110: ...A 10 Appendix A Path Evaluation Information Moseley SL9003Q 602 12016 01 Revision J ...
Page 118: ...D 2 Appendix D Microvolt dBm Watt Conversion 50 ohms Moseley SL9003Q 602 12016 01 Revision J ...