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Issue 1.0 SPARE PARTS & MAINTENANCE POLICY 03/01 Page 10-1 Maxon SP200/210 Radio SP200/210 10.1.1 Component Replacement Surface mount components Surface mount components should always be replaced using a temperature controlled soldering system. The soldering tools may be either a temperature controlled soldering iron or a temperature controlled hot-air soldering station. A hot-air system is recommended for the removal of components on the multi-layered boards used in the radio. With either soldering system, the component manufacturer’s recommended temperature should be maintained. The following procedures outline the removal and replacement of surface mount components. If a hot-air soldering system is employed, see the manufacturer’s operating instructions for detailed information on the use of your system. CAUTION: Avoid applying heat to the body of any surface mount component using standard soldering method. Heat should be applied only to the metalised terminals of the components. Hot-air systems do not damage the components since the heat is quickly and evenly distributed to the external surface of the component. CAUTION: The CMOS integrated circuit devices used in this equipment can be destroyed by static discharges. Before handling any of these devices, service technicians should discharge themselves by touching the case of a bench test instrument that has a 3-prong power cord connected to an outlet with a known good earth ground. When soldering or desoldering a CMOS device, the soldering equipment should have a known good earth ground. Surface mount removal 1. Grip the component with tweezers or sill needle nose pliers. 2. Alternately heat the metalised terminal ends of the surface mount component with the soldering iron. If a hot- air system is used, direct the heat to the terminals of the component. Use extreme care with the soldering equipment to prevent damage to the printed circuit board (PCB) and the surrounding components. 3. When the solder on all terminals is liquefied, gently remove the component. Excessive force may cause the PCB pads to separate from the board if all solder is not completely liquefied. 4. It may be necessary to remove excess solder using a vacuum de-soldering tool or solder wick. Again, use great care when de- soldering or soldering on the printed circuit boards. It may be necessary to remove the epoxy adhesive that was under the surface mount component and any flux on the PCB. Surface mount component replacement 1. “Tin” one terminal end of the new component and the corresponding pad of the PCB. Use as little solder as possible. 2. Place the component on the PCB pads, observing proper orientation for capacitors, diodes, transistors, etc. 3. Simultaneously touch the “tinned” terminal end and the “tinned” pad with the soldering iron. Slightly press the component down on the board as the solder liquefies. Solder all terminals, allowing the component time to cool between each application of heat. Do not apply heat for an excessive length of time and do not use excessive solder. With a hot-air system, apply hot air until all “tinned” areas are melted and the component is seated in place. It may be necessary to slightly press the component down on the board. Touch-up the soldered connections with a standard soldering iron as needed. Do not use excessive solder. CAUTION: Some chemicals may damage the internal and external plastic parts of the radio. 4. Allow the component and the board to cool and then remove all flux from the area using alcohol or another approved flux remover. 10. SPARE PARTS & MAINTENANCE POLICY -Issue 1.0 Page 10-2 03/01 SP200/210 Maxon SP200/210 Radio Surface mounted integrated circuitreplacement Soldering and de-soldering techniques of the surface mounted IC’s are similar to the above outlined procedures for the surface mounted chip components. Use extreme care and observe static precautions when removing or replacing the defective (or suspect) IC’s. This will prevent any damage to the printed circuit board or the surrounding circuitry. The hot-air soldering system is the best method of replacing surface mount IC’s. The IC’s can -easily be removed and installed using the hot-air system. See the manufacturer’s instructions for complete details on tip selection and other operating instructions unique to your system. If a hot-air systems is not available, the service technician may wish to clip the pins near the body of the defective IC and remove it. The pins can then be removed from the PCB with a standard iron and tweezers, and the new IC installed following the Surface Mount Component Replacement procedures. Provided that the IC is relatively new, It will not be necessary to ‘tin’, all (or any) of the IC pins before the installation process. If the IC has been in stock for some time, cleaning, and tinning of the pins may be necessary. Issue 1.0 SPARE PARTS & MAINTENANCE POLICY 03/01 Page 10-3 Maxon SP200/210 Radio SP200/210 10. SPARE PARTS & MAINTENANCE P...

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