It's important to lay flat correctly the components to solder on the printed circuit before soldering. To do so you can:
On this image, we see a component (a resistance) maintained in place with adhesive tape.
Another technique to maintain the component is to slightly fold the legs.
Before soldering a discrete component, of type resistance or diode, you must carefully fold the legs to 90° at the good length. The rounded form of the fold must be as small as possible (flat tongs are indispensable to perform this task). With a little experience, you'll know where you must realize this fold so that the component passes without effort in its seating holes.
Begin heating the base of the leg of the component during one or two seconds, then apply, while heating, the soldering at this base. One or two seconds are sufficient to get the component soldered. Then take away, at the same time, the soldering thread and the soldering iron. It's not useful to insist on heating the component during many seconds. Over 5 seconds heating, you risk deteriorating the component or make the plastic holders melt. If the solder seems not satisfying, you only have to wait for a while. Then start again putting a little soldering again.
It's important that the extremity of the pane be clean, glittering and smooth. Every 5 or 6 solders you must rub it on a humid sponge. If, despite the cleaning on the sponge, the pane has still traces of soldering in the form of little roughnesses and if it looks lustreless, melt a little soldering thread on the pane. Then try again on the sponge (this process is called tinplating). The cleanness of the pane is a golden rule to manage good solders. An appropriate temperature for the soldering iron is situated between 350 and 370°C. The pane of the iron must be thin. Use a quality model of soldering, without cleaning and with a little diameter (0.5 mm).
The iron in one hand, the soldering in the other, you have all the cards in hand to build your camera.
A bad soldering is distinguished by his grayish aspect or because it takes the shape of a bullet. A good soldering is glittering and forms a small cone around the soldered leg.
The worst is the so called dry solder. Often, the origin is an insufficient heating of the leg before the application of the soldering, or a movement of the component while you are soldering it. Outwardly, the component is soldered. But in practice, it's only stuck. The dry solders at the origin of bad contacts, sometimes hard to find out. You won't make any dry soldering if the pane of the iron is clean. If you think you have done a dry solder, you only need to reapply the soldering iron on the ill leg, then heat for one or two seconds, and as you are here, put again a little soldering.
If you solder a component at the wrong place or reversed, you must unsolder it. For this, use unsoldering braid. It has the property to capture the soldering and so to release the legs of the component. Apply the extremity of the braid on the solder, and the soldering iron on the braid, during several seconds. It's uncommon that all the soldering be aspired at one time. You shouldn't insist too much: cut the extremity of the braid having pumped the soldering and start again.
The braid is applied on the solder you want to get rid of. With the iron, we press on it hard enough during 4 or 5 seconds.
A good lighting is indispensable. Put together the components around you in order to go on quickly. Have a minimum organization.
It's convenient to know how to read the colored rings on the resistances. Even
if it's always possible to measure the value with a digital voltmeter on the
ohmmeter position, it's quicker to decode the message of these rings if you
mix components with different values. The colors of these rings are read starting
with the one closest to the edge of the resistance. Here is the correspondence
between the color and the associated value:
For example, if a resistance includes the following colored rings: brown, black, red, silver, its value is 10 followed by 2 zeros, so 1KW with a 10% tolerance. Another example, a 220W resistance with 5% tolerance will be represented by the following colors: red, red, brown, gold.
The value of the tentalum drop capacitors is indicated on the body of the component. A second figure gives generally the maximum tension to apply to the capacitor. In Audine, this value, 25V, is common to all the polarized capacitors. Take great care of the direction of the assembling of these components: the + leg is designated by a line.
The ceramic capacitors have no assembling direction. Their value is either directly indicated in picofarad or in nanofarad, or defined by 3 numbers followed by a letter. The two first numbers correspond to the two first digits of the value of the capacitor. The third number is a multiplier by a power of ten in picofarad. The letter designates the tolerance, K for 10% and M for 20%. For example, if the inscription on the capacitor is 102K, the value is 10 multiplied by 100 picofarads, so 1000 picofarads, or 1 nF.
For the diodes, the reference is indicated on the body of the component (it's written small, a magnifying glass is sometimes useful). The extremity corresponding to the cathode is designated by a ring. On the electrical charts, the cathode is represented by a line at the extremity of the symbol.