Grounding Issue -- Unfriendly ghost notes

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Grounding Issue -- Unfriendly ghost notes

Postby shuey79 » Mon Apr 08, 2013 12:35 pm

Looking for any pointers on why I'm getting a lot of ghost notes? I think I have a grounding issue. The case is steel but the front part where the lcd mounts is aluminum. When the lcd is mounted I get a crazy amount of ghost notes. When I remove the lcd from the mounting and let it float in air I still get them but the amount of them dramatically decrease.
I have both main boards isolated by some foam adhesive (you can see this in the pictures). There are 4 metal screws mounting it to the case-1PIN1, 1PIN2, 1PIN3, 1PIN4 and according to the multimeter they are grounded to case. .
The grounds for all 1/4 jacks go to grounding terminal (bridged) then to Pads Connector 1 using wires #15 & 16. 15 & 16 are tied together then run to this terminal block. This terminal block is mounted to the case. To clarify, the boards, wires 15&16, and all jacks are grounded to the case -- as checked with multimeter.
I thought it was an issue with the way I mounted the usb so I ran a ground wire from the terminal block to the case of the usb jack. It did nothing-- see pictures. I started checking the pins for the usb jack and see that the ground there is not the same as the ground for the case-- you can see in the picture.
Putting pictures on my msn gallery because I don't want to shrink them too small. http://sdrv.ms/16EdV11

I'm kinda stuck. When megadrum is taken out of the case the problems go away.
shuey79
 
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Re: Grounding Issue -- Unfriendly ghost notes

Postby dmitri » Mon Apr 08, 2013 12:51 pm

shuey79 wrote:I'm kinda stuck. When megadrum is taken out of the case the problems go away.

Starting from here, and using the kit's original USB break out cable, put one piece at a time into their destinations.
1. Mount LCD. Did problem appear?
2. Mount the Controls board. Did problem appear?
3. Mount the Positionl board. Did problem appear?
4. Mount the the main board. Did problem appear?
5. Mount the power switch. Did problem appear?
6. Switch to your own USB break out cable. Did problem appear?

Also, judging from the pics, the marked wire of the flat inputs cable is connected to pin 40 of the pads connector on the positional board, where is in the kit's manual the marked wire goes to pin 1. Make sure you connect your input jacks taking this into account.
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Re: Grounding Issue -- Unfriendly ghost notes

Postby shuey79 » Mon Apr 08, 2013 5:36 pm

dmitri wrote:
shuey79 wrote:Also, judging from the pics, the marked wire of the flat inputs cable is connected to pin 40 of the pads connector on the positional board, where is in the kit's manual the marked wire goes to pin 1. Make sure you connect your input jacks taking this into account.



Looks like this was the issue. There weren't any numbers on the positional board and couldn't find the board in the manual. After looking for it on the site I discovered that I'm an idiot! Quiet as a mouse now!
As for all the other connections I have been making sure its #1. Not sure why I dropped the ball on that one.
Thanks
shuey79
 
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Re: Grounding Issue -- Unfriendly ghost notes

Postby Nepo » Tue Apr 09, 2013 3:11 pm

Hello,

sorry for this rookie question (nonelectrical).

When I use a aluminium housing must the kit complete isolate or must this

grounded with the housing?

Thanks in advance....
Nepo
 
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Re: Grounding Issue -- Unfriendly ghost notes

Postby dmitri » Tue Apr 09, 2013 3:48 pm

You must avoid any metallic part (except ground) in the kit touching anything metallic on the case.
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