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The point of the production

Assembly procedure

	The jumper wiring that is hidden by the parts is attached in advance.
	Naturally, the jumper wiring that passes under the parts( e.g. Under the IC socket ) is attached in advance. Later it is not attached.
	The assembly of the circuit board is done to the left from right, or to the right from the left.
	The parts are not mount on the circuit board at a time. It mounts and assembles one each. This is to assemble without mistaking the interval of the part and part. And it is to secure the space where attaches the part.
	It attaches from the short part.
	When the tall part is attached first, the short part becomes difficult to attach. The electrolytic capacitor or transistor is tall part, the resistor or diode is short part.
	One part is mounted, then you do the soldering.
	Soldering is done to fix the part. But wait a moment to sloder the all component leads.
	If the part is mounted, you solder the wiring between the parts together.
	The turn needs to be considered of soldering of the component lead. When it mistakes, the hole of the circuit board that passes the component lead of the part by soldering has been closed.

Attention when the part mounting

There is the direction where the part mounts that it depends on the part.

Electrolytic capacitor/Tantalum capacitor

The electrode of minus and the electrode of plus are decided.[Polarised]


Diode

Pay attention to the direction of the anode lead and the cathode lead.


ICs

Pay attention to the direction of mounting.
In the case of DIP, it becomes a turn from the 1st pin from the left to the right on the side of under seeing from the top and the mark of the hollow is done left.
The upper side becomes from a young No.(right) to an old No.(left). The counterclockwise number is attached.
In the case of pattern drawing, it assumed that you see it from the wiring side (the reverse side) of the circuit board. Then the attention is necessary, because the right and the left are sometimes mistaken.
I sometimes mistake.


Transistor

In the case of type such as 2SC1815, that the center lead is a collector understands right away.
But I sometimes see the base lead and the emitter lead conversely.


Three terminals voltage regulator

In case of 78L type, the center lead is a ground understands right away.
But I sometimes see the input lead and the output lead conversely.
In case of the other type like 79L, 78xx or 79xx, the pin connection is different. So, you must check with the data sheet.

Light Emitted Diode

There are many cases anode lead and cathode lead do not understand.
The long lead is a anode side( connect to plus voltage ) in the case of a new article.

The point of soldering

A little point is necessary for soldering. When it was a beginning, I think that it can not skillfully. When you train it, I think that gradually the point understands.

Temperature of soldering iron

It does not get warm right away even if soldering iron is connected to the power supply. For a while you wait. When it does several minutes it gets warm.
Solder is attached in the top of soldering iron, and if it melts right away, it's OK.


Handling of soldering iron

Soldering iron handles with the point that has a pencil.


Part of previously hot that does soldering is made

Soldering iron is attached to the place of the part and printed board that do soldering. At this time, solder does not attach yet.
Even with, this action is several seconds. When it is long time the part has been broken.
The part needs to make the temperature that solder melts.
Little experience is necessary to this timing.


Soldering

While keeping the position of soldering iron, the solder wire is attached to the part that became hot.
Solder melts and spread to the part and the printed board. The feeling that was able to apply solder instead of attaching is good.
Solder does not need to attach a lot. Although it depends on the place that attaches solder, it is good to become the form of the slope of Mt. Fuji that is a famous mountain in Japan. Do you know that?
It does not become a slope with the surface tension of solder in a small place.



Mt. Fuji





Remove the solder and soldering iron

If the component leads of parts, wires are connected to the circuit board by the solder, you remove the solder wire and soldering iron from there.
It is no problem, if you remove it simultaneously, but the finish is beautiful when the solder wire is removed in advance a little.
If the soldering iron is removed in advance, the solder hardens right away, then the solder wire is fixed to the contact point.


Repair of solder

There is case sometimes, soldering is not sufficient.
Too many solder, too few, bad the form, bad the color etc.
Such case, it repairs by soldering iron once again. You may not go skillfully even if it repairs only with soldering iron.
To case like that, it is possible beautifully if the solder wire is applied furthermore to the place of solder that is melting by the soldering iron.
Even with, gradually the volume of solder increases. Then it is better to use the solder sucker for decreasing the volume of solder.


Solder sucker

The solder when attach to the part once can not remove completely like before. ( It has no way but to shave it )
Even with, the volume of solder is able to be decreased.
Even in the case that the part that did soldering once is removed this method is able to be used.

Using the desoldering wire
Desoldering wire is applied to the place that wants to decrease the volume of solder.
The desoldering wire is made with the net of copper wire and be doing the copper color. It becomes a silver color when solder is absorbed. When you absorbe the solder, the place that is doing the copper color is used.

Soldering iron is applied from the top of desoldering wire, then the solder that was attached to the part is melted.
Solder that melted is absorbed to desoldering wire with a capillary tube phenomenon, then the desoldering wire has become a silver color from the copper color.
In the case that it is not able to absorb once, It absorbs while shifting desoldering wire.
The place of desoldering wire that absorbed solder cuts with cutter and discards, because it is not able to use with twice.

Using the solder pump
Solder pump is the instrument that did a cylinder form. Spring and piston are included into the cylinder.
Moving the piston with the power of spring solder is absorbed.
As for the usage, see the page of the instrument.
The solder pump is able to take solder more quickly in comparison with soldering wire.