Omega2 almost DoA



  • I'd like to share on what I learned on my Omega 2 Plus unit. When I received the board, I noticed there are a few solder balls and splatters on the PCB or near the 2mm pitch connector pins. I immediately rubbed them and took them off. Then I tried to power it up but the amber LED never lit nor blinking at all. If I used a lab bench power supply with 3.3V direct-powering, the current consumption is just 20mA and the metal RF shield never gets warm. I also used a min-dock with microUSB powering. USB power meter showed current consumption increased for about 20mA (at 5V), also no amber light nor warming up. After struggling for awhile and checking on published data, I became suspect the Omega2+'s pin 16 (lower left corner) Reset_B (or RESET) is grounded to the PCB trace that is grounded thru a solder splatter. It really looked like a circuit trace. I used a Xacto knife to take it out and now it is working normally (consuming 3.3V 170mA, getting warm, and amber LED blinking then stable.) BTW I found out that in my PCB, pin 25 Net_POW (right side, the 8th pins counting down) is not connected to anything as oppose to 3.3V power output shown in the PINOUT Diagram. Actually on PCB, there are two reserved zero-ohm resistor positions, none populated. One is for 3.3V out and the other some type of logic IO. Hope this info is useful for some and possibly save an RMA.



  • Adding a picture showing the solder splatter
    0_1483120322404_DSC02282.JPG



  • Oh! That's small... I'm going to perform a VCC-GND loop test on everything I get... before powering anything up. Hopefully, the tests will all fail. ;-) I received my tracking number today so I'm next in line.



  • @ccs-hello you just saved my day! I had the very same error, but on the other side of the PCB. I can't believe how sloppy these guys must have been? It looks hand soldered to me? It boots now and my el-cheapo shield with power/serial worked perfectly :)

    I've spent so much time on this with absolutely no help (quite the opposite actually) from the Onion ppl. If you try to report your problem through official issue tracker, you'll enjoy incompetent advice from people that don't read through what you already tried. Two different persons suggested that I do things I've already done and when I replied, they closed the ticket? Oh well. Much better advice from the users of the product I guess. This completely solved the problem that I had, so thanks for posting!

    here's my soldering error



  • Soldering by hand is perfectly acceptable imo, but it absolutely has to be performed by an experienced technician. The work on your board is VERY SLOPPY. This is very disappointing!

    The problem with offshore work is that we loose expertise locally for sustained year-round work. And when problems occur, it's much tougher to solve because of the distance. I don't like this international economics model.


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