Ramsey Electronics UAM4, Руководство пользователя

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UAM4
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For each part, the word "Install" always means these steps:
1. Pick the correct part value to start with.
2. Locate the correct PC board location.
3. Orient it correctly, follow the PC board layout drawing (page 24)
and the written directions for all parts - especially when there's a
right way and a wrong way to place it on the board. (Diode bands,
electrolytic capacitor polarity, transistor shapes, dotted or notched
ends of IC's, and so forth.)
4. Solder all connections unless directed otherwise. Use enough heat
and solder flow for clean, shiny, completed connections.
SURFACE MOUNT(SMT) COMPONENT SOLDERING INSTRUCTIONS:
You’ll notice that the circuit board contains only a few holes for component
leads to pass through. This is because the SMT components will be affixed to
the “solder” side of the PC board, the side with the white lettering or ‘TOP’. Be
aware that the component view for assembly is looking at the ’TOP’ side of the
PC board. Patience is the key when installing surface mount components!
Typically, the first step (after identifying the component) is to “tin” one of the
PC traces that will connect to the part. Once this is accomplished, the part can
be installed by holding it with tweezers in contact with the “tinned” trace and
re-heating the solder. Another commonly used technique is to glue the surface
mount components to the printed circuit board before soldering. The
procedure is to take a small amount of glue (usually with a pin or toothpick)
and “dab” the circuit board in the place where the component will be affixed.
Be careful not to apply too much glue as when the part is placed it may
“squash” the glue underneath the soldering tabs of the component. Carefully
place the part into position, and when the glue dries, solder the connection.
This may go a little “against the grain” at first, but it is by far the easiest
method. Notice also that when reheating the solder that the iron tip does not
come in contact with the “tab” on the body of the chip component. Over
heating of this solder tab can cause a fracture of the bond to the component,
causing an intermittent connection.