JA board not working

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Hi all

I am doing a build and have got to testing the JA board. Mine is not working; I just get random behavior with different combinations of LEDs turning on and off, blinking, etc. I have checked everything I can think of on the board and it looks okay to me. This is my first time doing surface mount but I thought it went okay. Alo checked the orientation of all the diodes.

I posted a video of the behavior here:

I’ve attached a few photos of the SMT IC and resistor network to show the connections.

Any ideas of what I can try next?

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At least three dry joints on the legs of IC3 for a start (RN1 looks like it may have a few dry joints as well) - try some flux ?

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Thanks. I added some flux and redid each pad; still not working.

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Aaargh - I see what the issue is; exactly the same as the first one here: http://midibox.org/forums/topic/20993-troubleshooting-midiphy-seq-v4/http://midibox.org/forums/topic/20993-troubleshooting-midiphy-seq-v4/

Wrong resistor network. :-(

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After replacing the resistor network, still not working, but at least less erratic. I don’t seem to get any events from the buttons and the LEDs don’t light up. A twist of the encoder knob sends an absolute barrage of events to the debug log and makes the LEDs flicker momentarily.

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I see a lot of dry solder joints; are you using lead solder or lead free? I suggest to get a hot air rework station, even a cheap one would probably help here.

Possible causes for strange MIOS signals:

IC backwards or wrong type soldered
Resistor network backwards or wrong or wrong type soldered (as you found out)
IC pins shorted together, especially if there is a “sequential” increase in triggered events rather than random. The actual messages might tell you something.
Generally cold solder joints or poorly aligned ICs
Backwards or broken diode or LED