Almost every radio amateur is faced with the problem of an overheated soldering iron, when the tip heats up more than necessary. Soldering with such a soldering iron is not very convenient: the solder begins to change color, becoming covered with an oxide film, the flux instantly evaporates or even begins to shoot, etc. The way out can be very simple.
We need two things: a wired switch (which is attached directly to the wire) and a diode with a reverse current voltage of at least 250 volts and a current of more than 0.5 amperes (depending on the power of the soldering iron, based on 100 W = 0.5 A).
Let's start assembling. To do this, in a place convenient for you, you need to open the insulation of the current-carrying wire, namely one of the wires, and connect the switch. Install a diode into the switch, connecting it in parallel with the contacts of the switch. See the diagram.
We assemble, turn on, check.
The device works like this: when the contacts of the switch are closed, 100% of the power flows to the soldering iron, and accordingly the tip heats up by the same amount. This mode is used to quickly warm up the soldering iron.As soon as the soldering iron has warmed up (5-20 minutes), turn off the switch. When the switch is turned off, the current will flow through the diode, and the diode will pass only half of the alternating voltage phase and therefore 50% of the power, the temperature of the soldering iron will decrease.
I have a 60 watt soldering iron. The temperature in the second mode is excellent for soldering with the most common solders. I also had a soldering iron with a power of 100 and 30 watts with this regulator and it was also pleasant to work with them without overheating.
I would like to note that with the use of this simple regulator, I completely lost the desire to make more complex ones or buy expensive ones.
But still I want to offer one more option for the regulator. I haven’t used it myself, but friends say that this regulator works quite well.
Here's the idea. Electrical goods stores sell ready-made regulators, albeit for lighting devices. It looks a little larger than a regular switch and can be successfully used for a soldering iron. See picture.
The disadvantage of such a regulator is its “invisibility of adjustment”. In other words, if you use it for a light bulb, then you obviously see the level of adjustable brightness. But with the soldering iron everything is sad. You cannot visually surprise its temperature and you have to adjust it from time to time. But there is still a way out. You just need to simply calibrate the regulator and mark the positions with a marker.
Whatever regulator you choose, when installing or adjusting it, do not forget to disconnect it from the network! Good luck.
