Rosin flux

The Rosin flux can be used to detect broken parts on a PCB that would normally be overlooked before. The PCB should be cleaned beforehand with PCB cleaner. Then use the Rosin flux and smoke it over the PCB to let the smoke drop on the PCB. This is achieved by dipping the soldering iron into the flux and then holding it above the board. This has to be done a number of times to cover the entire surface.
A lab power supply is then used to locate the broken part.

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