Electronics Forum | Tue Mar 25 11:25:18 EDT 2014 | horchak
The first impression I get is that the mask was applied over dirty or contaminated copper. What is the trace and land finish on the PCB? You also appear to have a wetting problem.
Electronics Forum | Tue Mar 25 11:43:48 EDT 2014 | sara_pcb
It is Solder Mask on Bare copper, The land finish is HASL as per MIL-PRF-55110G which accepts trace of HASL as acceptable. Wetting is acceptable. regards, R.Saravanan
Electronics Forum | Mon Dec 17 14:16:44 EST 2007 | realchunks
This is funny. Poeple giving answers to a question that isn't specific. What if the shorts he is having are on the top of his board, caused by flooding or Omega wave too high?
Electronics Forum | Fri Feb 13 11:46:23 EST 2004 | Jack
Is your customer trying to reduce voiding? If the device is using Sn90 / Pb10 and the paste is Sn63/Pb37 the board will melt first. However, if both solders are 183C eutectic, it's a tossup? PCB design, copper weight, bga type (pbga, micro bga, Tbg
Electronics Forum | Mon Jul 28 14:30:22 EDT 2008 | grics
Take a look at this. Remember, these are only guidlines and can not replace any paste specs. As Real Chunks said, a profiler will be of HUGE help. We use this to determine what our top side temps are and to see if we have any problems with heat sen
Electronics Forum | Fri Apr 20 07:12:22 EDT 2001 | wbu
Dougie, oh yes, it�s a bit short that chapter. I have the Revision e in front of me and this one contains in the appendix the needed IPC-TM-650 Test method for bow and twist. Can�t think that they don�t have that in the new revision. Hope you find
Electronics Forum | Fri Apr 20 07:30:14 EDT 2001 | wbu
In short: the measured deviation / the length this deviation occurs * 100% = % of deviation Actually we encounter mostly "twist" so we put the board on a flat surface, hold it down at the corners to see if any of the corners lifts, measure the heig
Electronics Forum | Fri Jun 04 14:03:18 EDT 2004 | Frank
I know Juki has the headquarters in NC, but they have a support office in the Silicon Valley with spare parts. I know they go to the NW area quite often from that office. They offer their customers 7-day/24-hour free phone support (including holida
Electronics Forum | Wed Feb 01 22:27:16 EST 2006 | KEN
Many relays use soldered post coil terminatins inside the relay. In one case many years ago I found the SMT relay manufacturer used eutectic solder inside their hermetic relay. The SMT relay would fail because the solder balled up on the post, woul
Electronics Forum | Thu Mar 25 12:24:12 EDT 2010 | ssager
When testing components on a PCBA, try to validate coverage for presence, correct, orientation, live, and alignment. AOI is not really great at catching cold solder joints and damaged components, and from my experience an X-Ray is only as good as the
