Build Your Own Arcade Controls Forum

Main => Main Forum => Topic started by: grippie on November 03, 2015, 01:16:38 pm

Title: PCB soldering problem
Post by: grippie on November 03, 2015, 01:16:38 pm
So I broke apart my game gear pcb for my portable pi project, and the d-pad isn't functioning properly... I think.

If i take my multimeter and check for continuity by putting black on the common ground, and touching red to the wires i get weird results.

For up. Left. Right.  It zeroes out the multimeter which doesn't seem right. If i check down, it doesn't zero out until i press the pad down to complete the connection.  The right side buttons seem fine, only zeroing out when the button is engaged.

Any ideas? The pic shows the solder points that I'm checking with the multimeter.  Pic is from the adafruit project that i based my cuts on.


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Title: Re: PCB soldering problem
Post by: grippie on November 03, 2015, 01:18:39 pm
Here is my actual work but the glue obscures the solder (which i checked and isn't bridged)


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Title: Re: PCB soldering problem
Post by: lilshawn on November 03, 2015, 02:26:00 pm
can you verify the "ground" is in fact common to all the pads and not a seperate line in itself?
Title: Re: PCB soldering problem
Post by: Slippyblade on November 03, 2015, 03:21:57 pm
can you verify the "ground" is in fact common to all the pads and not a seperate line in itself?
Yeah - gonna agree here.  Sounds like the ground is split up, which isn't uncommon.
Title: Re: PCB soldering problem
Post by: BadMouth on November 03, 2015, 03:56:41 pm
Still, it sounds like the top 3 are grounded out.
Could we see the flipside?

Title: Re: PCB soldering problem
Post by: grippie on November 03, 2015, 11:43:22 pm
I think i have a bridged trace somewhere.  I desoldered the wires and tested one by one and got 3 of them working ( all but dpad left). Im not sure yet why the last one isn't working. I think i may have oversoldered and bridged the common ground and my one trace. Im trying to scrape back the green layer to get directly at the traces and away from the crappy solder pads which lifted.   


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Title: Re: PCB soldering problem
Post by: SavannahLion on November 04, 2015, 12:02:27 am
You can get the schematic here: http://gamesx.com/wiki/doku.php?id=schematics:console_related_schematics (http://gamesx.com/wiki/doku.php?id=schematics:console_related_schematics)

Looks like common grounds with caps for debouncing. Not sure where the M# leads go off to.

Hope those schematics and notes help.