Dangerous Prototypes Open Source Hardware

LM339 is my favorite. However, I cannot guarantee that it will work better nor worse than minkok's one. Their performance on the simulations are almost the same.

There is LM393 in DIP8 package. 2 comparators inside - just enough for one input.

...and maybe TLC393 - it has FET inputs and 10000 times lower input bias currents.

Hello, Sparky. The sleep board I'm using now is cd4001 with interference. Affect the use. Now to take a look at the results of the design of contact dormancy. Please tell me how to choose?

LM339？ 74LVC2G132?  HEF4093?How should I choose the SCH of these three ? thank you!!!

Hi, first of all, thank you very much for opening the source project, and then I would like to ask if you can update support for JBC470 and HAKKO T22. I am looking forward to your update of JBC470

Which version sensor board are you using? Minkok's design with BJT + MOS should work fine so you probably are using older?

Upload a photo and maybe we can help you to modify rather than build new

What prevents you from simply inserting the 470th sting into the 245th handle, I checked it and it works great, although it does not heat up at full power, but the sting has a different heat capacity and it also plays a little role.

No change still unable to calibrate and power source is detected as DC.

Thank you. Cd4001 is still not ideal after many times of optimization. Now that sparkybg has designed a new Sch, I decided to try it out. Rather than continue to optimize. As for the interference problem, the program can not feel it, but my friend modified the program and added a state. So it can be seen that the source of interference is contact with the dormant board. When the power is turned on, the interference will occur at full power, as long as it is not full power.

Forget about fake HAKKO FG-100 - I have it - total crap! It shows 170 degrees while 63/37 solder is melting on it's sensor at it's eutectic point of 183 degrees. And it loads the tip. The smaller the tip, the larger difference there will be from when there's only a drop of solder on the tip.

Get 63/38 solder with nothing else (melts at 183), and watch only when solder starts to melt on the tip! Then get pure lead (melts at 327.5) and watch it again.

Before starting to observe the melting point, wet the tip and clean it several times with what you will observing, in order not to have residue from something else on the tip.

And, if handle is at 40 degrees at the contacts - this is normal. Then 18 degrees are subtracted from tip's temperature. JBC tools does not have a temperature sensor in the handle so the only temperature that can be used for cold junction compensation is room temperature at front PCB's sensor. Nothing can be done about his

Fortunately in my enclosure the temperature goes to around 5-6 degrees above room, and this tracks the handle temperature to some degree.

That's why I am considering an option in the menu for room temperature override.

For the cold junction compensation part, when the room temperature is about 26 degrees, the measured value of the main board is 32 degrees, and there is a deviation of 6 degrees. I don’t know if this room temperature can be calibrated in the program to make the cold junction compensation relatively more accurate.

Even if youmake it show real room temperature, the iron's handle (where the cold junction really is) handle heats up a little, so in fact this heat-up of the front PCB is in fact beneficial to some degree.

If there is no sensor in the handle itself (like PACE and Weller), nothing can be done to eliminate the problem completely.