Sanwa PC20TK, Инструкция по сборке и эксплуатации

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21
2. Chip component
Solder
0.5 second
Fig. 4-2
0.5 second 0.5 second
Solder
Solder
Solder
1
Apply a small amount of
preliminary solder to one
end of land.
2
Amount a component and
press it with your fingers.
3 Melt the preliminary solder
with the soldering iron tip to
solder the component.
4 S o l d e r t h e o t h e r e n d b y
applying the soldering iron
tip and solder.
4-3 Precautionary instructions for assembling
1. For an LSI, avoid touching any of its pins, wherever possible, because it might be damaged
electrostatically. In particular, care must be taken in the winter season when static electricity is
more likely to be generated under the dry condition.
2. In the 750 VDC or VAC range or the 40 M
Ω
range, the circuit resistance is so high that a leak
might take place. Avoid touching the surface of a printed circuit board with a bare hand,
wherever possible. Prior to work, be sure to wash your hands and dry them.
3. A printed circuit board is of through holes. If any incorrectly mounted component is removed by
pulling it with excessive force, the continuity between the top and the bottom is broken.
4. If solder is not successfully absorbed with a solder absorber, apply additional solder to that part
and then try to absorb the increased solder.
Memo : The time required to hold the soldering iron tip on the part to be soldered varies
depending upon the size of the component to be mounted. Use the time values shown
in Figs. 4-1 and 4-2 for reference only.
4-4 Color codes and symbols of components
1. Identifying a resistor
[Example of identifying a precision resistor: 500 k
Ω
F] [Example of identifying a consumer resistor: 500 k
Ω
J]
5 0 0 k ±1 %
5 0 0 10 3 ±1 %
Green Black Black Orange Brown
±100 ppm/°c (±0.01 %/°c)
(Orange)
Color
Black
Brown
Red
Orange
Yellow
Green
Blue
Purple
Gray
White
Gold
Silver
1st color band 2nd color band 3rd color band 4th color band 5th color band
1st numeral 2nd numeral 3rd numeral Multiplier Tolerance
0
1
2
3
4
5
6
7
8
9
10 0
10 1
10 2
10 3
10 4
10
5
10 6
10 7
10 8
10 9
10
-1
10 -2
−
±1 %
±2 %
−
−
±0.5 %
±0.25 %
±0.1 %
−
−
±5 %
±10 %
5 0 0k ±5 %
5 0 10 4 ±5 %
Green Black Yellow Gold
1st color band
1st numeral
2nd color band
2nd numeral
4th color band
Tolerance
3rd color band
Multiplier
Symbols showing tolerance
B : ±0.1 %
F : ±1 %
K : ±10 %
C : ±0.25 %
G : ±2 %
M : ±20 %
D : ±0.5 %
J : ±5 %
Fig. 4-3(a): Example of identification of resistor
1 2 3 4
Temperature characteristics
(The 6th color band may
sometimes be omitted.)