| Right now,we have some problem on SMT. Cause of the flux residue | in the connector. Do somebody have the same symptom? By the way, | can i find something to make the flux observe easy or take a photo with the flux. | | | Unfortunately, this problem is all too common! :-(
Please provide more details (connector type and design, fluxing and soldering method and conditions etc.)
As for rendering flux residues visible, this is not easy. One way you can try is to buy an alcohol-soluble dye, such as propyl red (red) or alizarin (deep yellow) and make a strong solution in methanol (very toxic). Dip the suspected parts in it very briefly. The dye should colour flux residues more than the metal: of course, this will also colour everything else! Much better, incorporate a fluorescent marker in the flux (easy with liquid fluxes, less so with pastes - you would have to ask the manufacturer to do it) and examine the connectors under UV "black" light. Any residues would stick out like a sore thumb!
Brian
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