Quote from: philipma1957 on October 02, 2015, 03:19:37 AM

Quote from: sidehack on October 02, 2015, 03:17:17 AM

Nothing leaves my bench without the LED flashing properly on shares. I'd suggest checking on the connection state of the small diode inbetween the SOT23 transistors to the left of the LED. That circuit basically acts as a timed pulse generator triggered by the RX to kick on the flash, and if the diode for some reason lost contact you'll get green only.

That diode is one of the hardest parts for the machine to place correctly because it's such a friggin' small package, smaller even than the 0603. It's the littles thing on the board.

The bulk of rework-requirement issues is, I'm fairly certain, due to the solderpaste we used. It got lost in shipping and arrived a few days late, in August, which meant the ice pack it was shipped with to keep the binder from evaporating was mostly a wasted effort and it's pretty dry. Doesn't spread evenly, has no tack, and by the time parts are placed it's basically cakey dust which means adhesion sucks.

The pick-and-place had a bit of a learning curve and took some calibration and such to get going. It was about four days before I had it figured out enough to place a whole panel of 30 sticks, and about two weeks after that before I had things straightened out enough that it could place a whole panel without requiring manual intervention for some things. I'll be optimizing placement speed on the next batch, and with better solder paste and a bit more calibration things should stay pretty nice.

Issues like the shifted capacitors are actually a result of a bit of rework I have to do on the big FETs, partly because the solder paste doesn't stick to the pins without help. I started watching specifically for that, and on the last four hundred or so sticks have been making sure to manually align the caps and add solder when necessary.

We did use a different board house for the full batch. The V0.4 were from a quick-turn prototype outfit, but the production V0.5 were ordered from the same US fab place we get 750W PSU boards from. I wasn't expecting the vias to be so huge, and that actually adds to some of the soldering problems, especially on the big FETs - some of the pads have vias adjacent or internal which wick away melted solder and can leave the pad fairly dry. I'll have to take this into account on future designs.

well I am 20 for 20 with the green so i am not complaining tomorrow I get new psu in for my stud hubs. direct replacement and eff goes from 78% to 85%

the 2 hubs were doing 105 watts they dropped to 90 watts. any sticks left maybe i can get some more and fill the hubs up