In the last post I mentioned KSGER soldering stations, I mentioned buying two more, and one of the new soldering stations released the magic smoke. My old KSGER soldering station is my trusted soldering station, still working perfectly fine. But those newer ones,

The thing is, back then, after one of my soldering stations released the magic smoke, I ordered two bare soldering controllers, without the housing, as I already have the housing from the one that released the magic smoke. I wanted two, to have two boards of the same hardware revision, to compare the stock firmware with an open source replacement. For a fair comparison, the hardare should be the same, right? Also, I was interested in the mod to make them work with JBC style tips rather then the Hakko T12 style tips.

I have to admit, this still has been catching dust for months.Back then, I ordered two boards, one with and without the soldering iron connector on the PCB. The reason for this is the JBC mod. When those boards without housing arrived, it turned out to be a different PCB revision then the ones inside the housings I’ve got. This board has printed “Ver 3.3” on the silkscreen, and the firmware things it’s a 2.1S board. The board doesn’t seem to match any of the revisions documented online. As such, I couldn’t quickly find the 0R resistor to remove for the JBC mod.

In the meantime a new brand of soldering iron controllers for T12 tips popped up, Handskit branded. They are using the same connector as KSGER, but have a different pinout. Be aware! I haven’t tested much with this one.

But last week, I decided to put the board with the connector inside the housing. To do this, the connector has to be mounted in the front plate and then soldered. Thus, the board is soldered into the housing, and needs to be desoldered to be removed. Therefore I wished to test it before soldering it in. As the power cables didn’t match, I soldered the power cables in. First time after applying power, the screen came up with “ERROR”, which is to be expected with no tip connected. However, on the second test, nothing happened, the screen remained dark. So far, I haven’t seen any smoke, so not all is lost. Next, I tried to power the 3.3 Volt rail. This time the screen came up. However, the power draw was way more then expected. It drew half an amp, that is, on the 3.3 Volt rail, with no top connected. Something is running hot. To find out what, I sprayed some IPA on the board, and discovered the inductor labelled L1 was the component running hot. An inductor on this board is probably part of the DCDC converter circuitry.

The soldering iron controller I bought in October 2019 is still up and running., but, in the timespan of December 2021, I have received multiple failing boards. At least two out of four boards have failed one way or the other, and the remaining two remain untested. But with these stats, I have little confidence in them. In both cases, it seems the faillure is related to the DCDC circuit. The initial board had the DCDC converter release the magic smoke, so badly it burned a hole in the PCB. This one, well… the magic smoke is still inside, but there is something fishy going on. Might check what DCDC chip they’re using. Perhaps they’ve replaced the DCDC converter because it was out of stock, silicon crisis and all, and accidentality replaced it with a chip that can’t handle 24 Volts. Just some speculation. I might look into them later. For now, I’ve put all December 2021 KSGER stuf in a box labelled “DO NOT USE”.