Try to Remove the sleep PCB they are known to give issues that's why there are more than one version, if it works fine without Sleep PCB then try the new PCB from @minkok it works perfectly.
If by sleep PCB you mean PCB 15x25mm PCB that was included in package, i dont have it connected at all. And Im not even planning to, since it isnt neccessary?
I bought allready soldered together Unisolder from tindie. When assembling it, i mistakenly reversed polarity on DC input. I fixed this by replacing all 4 diodes for MBR2060CD. Unisolder springed to life. I am using it with JBC 245 (clone) and original JBC cartidges.
But there is still something weird happening: When I turn on the unisolder (after it has been turned off for at least 5 minutes) evertyhing works normally and OK. Cartridge heats up, and works perfectly. But if I swap cartridge it only says NO INSTRUMENT. Same thing happens if you turn off and back on station immediately after it has been powered on previously. Since I thought that this is obvious problem with handle, i soldered crocodile wires on connector. With that I learned something new: If you connect all 3 crocodiles on cartridge, you cannot get it to work except if you disconnect the "red" wire until it displays temperature (for very short time aka 0,5s) and then quickly reconnect it. This method works every time.
What can I check and or replace so that I could swap out cartridges and it would work normally? Tried reflashing sofware over usb from sparkybg github, no change in behavior.
When it actually works, it works perfectly. IMHO best soldering iron I ever seen
