Electronics Forum | Wed Jun 08 13:49:48 EDT 2011 | sonofptolemy
Hello, I am having a problem with HASL PCB's after it comes back from the stuffer. To me it looks like oxidation and it causes poor wetting. This leads to a bunch of problems all of which have different symptoms but the cause is this oxidation proble
Electronics Forum | Thu Aug 01 08:58:47 EDT 2002 | Rick Lathrop
Good morning Dave F. I am not going to try to touchup the solder pad until I get surface analysis work done, don't want to ruin the evidence. I am getting XPS work done not XRF, XPS is X-ray Photoelectron Spectroscopy and can see very thin films of o
Electronics Forum | Tue Aug 10 05:32:42 EDT 2004 | praveen_madaan@jabil.com
Hi, Has any body experienced the problem of poor cotacts on HDMI connectors. The connectors pins are gold plated and we see some kind of white residue on the gold pins.How to check if this is a flux residue?We are using No Clean flux in wave solderin
Electronics Forum | Wed May 24 16:57:23 EDT 2006 | Steve
The temperatures were measured on the board, ~1/2" away from the components in question. Admittedly the profile is on the bottom end of the Alpha recommendations. The profile was set up this way intentionally to avoid heat damage to other components
Electronics Forum | Tue Jul 30 17:47:50 EDT 2002 | davef
Dewetting: Solder does not adhere to lead or land, caused by: * Poor solderability of lands. * Poor solderability of leads. * Solder paste integrity. * Lead plating integrity. Need more information, please: * What is dewetting [ie, component, pad, e
Electronics Forum | Tue Jun 28 18:20:49 EDT 2005 | russ
Matt, have you run a profile on this board? Just because it's .062" doesn't mean that any old .062" profile will work. We have .062" thick boards that almost nil for copper and other are utilizing 2 oz. layers internally. They require quite diffe
Electronics Forum | Sun Sep 15 21:44:41 EDT 2002 | jason
Hi Dave, Immersion Ag has poor surface appearances after reflow or rather tarnished, while Immersion Tin requries higher temp. Probably that's why Immersion Ag is more preferred.
Electronics Forum | Wed Sep 01 08:27:38 EDT 2004 | davef
Zinc from the brass [Cu3Zn2] diffuses into the tin causing solderability problems. Just 0.001% of Zn in your solder can render it fit for the scrap heap. So, you need a barrier plate between the brass and the tin. Copper or nickel-plating is commonl
Electronics Forum | Fri Jun 14 14:30:36 EDT 2002 | davef
Assuming you are talking about solderable surfaces: People specify various materials to protect the solderability of the pads on the board. Gold, actually, Electroless Nickel - Immersion Gold [ENIG], is popular. * Board fabricators like it because
Electronics Forum | Sun Jul 29 08:36:39 EDT 2001 | davef
You have provided very little information. Two similar possibilites come to mind: poor pad solderability protection and old boards. POOR SOLDERABILITY PROTECTION: Maybe the nickel plating under the gold is oxidized, contaminated, or otherwise very
