Beste Ilse, Helemaal perfect, bedankt voor de snelle reactie. vriendelijke groet D.L.

Image shows scope trace of discharge process with 800mA fixed load, note that the 4.9V output is maintained for 32 seconds. Re-charge time (from zero Vcap volts with no load) was measured at 40 seconds.

The photos show the revision-A board under test,  the board works after some minor modification.  Revised schematics have been produced and new PCB artwork is currently being finalised.  Code for the PCI microcontroller is under development. The revision B board features improved functionality and some smaller, cheaper components.

@JohnHind @Russin Sir Bullar an upgrade is technically possible, but this would requiere to have just more than two requesting for it. If there is enough demand / interrest there may be the chance to have an improved / optimized version for more power™ Best Regards Mathias Claußen  

@Russin Sir Bullar Yes my suggestion above of using a desktop PC PSU would work really well here - easily 12v at 400W or more plus 5v auxilliaries all at very reasonable cost. I'd like to see two versions: 1. De-luxe desktop workstation with two 150W PWM soldering channels, ESD grounding (both on the irons and clips for mats and wriststraps) and 12V  and 5V auxilliaries for work-lights, fume extractors, USB charging etc. 2. Compact single-channel portable version powered by 18V power tool battery pack. It would be neat if the tip holder could have a built-in multi-colour LED for power and temperature indication (green at power-on running through to red when at temperature) and a touch-sensitive ring for auto on/off. Another neat feature would be temperature profile support: you would touch the iron cold to the junction and press a button on the tip holder which would trigger a pre-programmed temperature/time profile to mimic oven soldering.