i received the latest pre-production cards yesterday and have tested one of them: it works.
however (and this is the whole point of doing pre-production prototypes) in endeavouring to use automated assembly and solder paste it was discovered that the VIAs underneath the pads for the JAE DC3 Micro-HDMI connector are sucking the solder paste in and down, leaving the pins not properly connected.
the factory's engineer hand-soldered the 10 samples, but we cannot possibly do 1,000 PCBs by hand.... so it is necessary to do some test PCBs to work out how to get these connectors, with utterly tiny pins (0.25mm wide) to stick, given that the tracks simply have to come up from underneath using VIAs.
VIAs coming up on a pad is generally bad because it's a hole down which the solder paste simply... sucks down.
if anyone knows any tricks i would appreciate hearing them. i was thinking of creating the pad with a triangular end, placing the VIA right at the end so that the solder paste can't "wick away". anyone got any other ideas?
l.
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