Keyword: pcb Mounting, Pcb board
If you start soldering large components, pcb board they will block access to solder the next components. You should start from the small components, such as Surface Mount Devices (SMD) and end with the large components, such as through-hole capacitors or terminal blocks pcb board.
A cold solder joint is when, while making a solder joint, pcb board a hot solder flows onto a cold joint, and gives a greyish blob of solder that is not well adhered to the joint. It can also happen when not enough heat was applied for the solder to melt properly or the surface being soldered was not clean enough. Sometimes it can be seen with bare eyes (you will crack the solder joint if you try to move the pin), other times looks like a well done solder. The effects of these solder joints can be static noises, pcb board intermittant cutouts and others. To solve this, you can either remelt the existing solder or suck it out, clean the spot and solder again.
To avoid cold solder joints, first heat the joint with the tip of the soldering iron, then touch the joint with the solder. The hot joint will melt the solder and it will flow and engulf the joint properly. A nice way to avoid cold solder joints pcb board, and facilitate soldering in general, is to use flux. Soldering flux is a chemical agent that makes soldering a piece of cake. It does so by improving the wetting characteristics of the liquid solder. Just add some flux in the surface to be soldered and the hot solder will immediately glue to the pin. pcb board A normal multimeter has a continuity test mode that beeps when the resistance between the two probes is small. pcb board This is commonly used to test continuities, because you don't need to jump between looking at where you put the probes and at the value on the multimeter.
However, a resistance of a few ohms still beeps, although it is a sign of bad soldering. pcb board Assuming low resistance lines and a few solder points, pcb board the resistance should be below 1 ohm. Use the resistance measurement mode to guarantee that the resistance between two points is as low as it should be, which also means good solder joints.
