Midland 70-1341, Руководство по обслуживанию

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SERVICING
70-1341/1344/1441/1444
4. Place component and briefly heat the new solder and pad while holding the component with tweezers.
Do not touch the new component with the iron. Only heated solder should touch the component to make a
light "tack" bond to it. See
Figure 4 - 3.
Figure 4 - 3
Figure 4 - 3
5. With one component end tacked to hold it, the other end can be soldered. Carefully apply heat to the PC pad
while adding only enough fresh solder to produce a clean fillet as in Figure 4 – 4 — do not apply too much
solder, otherwise it may flow underneath and short the pads together. Let the hot solder flow onto the
component—do not touch the component with the iron. Repeat to finish the other end of the component.
Solder must adhere to all metallic end-surfaces on both ends as shown in
Figure 4 - 5.
CAUTION: Avoid direct contact to the chip component with the iron tip. Too much heat and contamination will
break down the metallic film on component ends resulting in loss of internal connection (a capacitor is comprised
of several wafer plates that connect through the metallic end-surfaces). If satisfactory solder adhesion does not
occur, the metallic end surface has been damaged and the chip component should be replaced again. More
soldering will only damage the component further.
Figure 4 – 4 Figure 4 – 5
4 - 5