madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: tenwatt on April 07, 2015, 11:35:35 PM

Title: Ground Issue?
Post by: tenwatt on April 07, 2015, 11:35:35 PM
(http://i980.photobucket.com/albums/ae285/guyskankrye/IMG_1208_zpsehnivfqt.jpg) (http://s980.photobucket.com/user/guyskankrye/media/IMG_1208_zpsehnivfqt.jpg.html)

This is an old one I stuck aside because I didn't wanna do the problem solving.  Rocked it before I boxed it.  Bypass works, LED works, no volume when I turn up the gain.  I'm wondering if my ground job just blows?
Title: Re: Ground Issue?
Post by: davent on April 08, 2015, 12:07:44 AM
Is it possible a power jack tab and output jack tab are making contact or a wire shorting in there abouts?
Title: Re: Ground Issue?
Post by: tenwatt on April 08, 2015, 12:17:47 AM
Quote from: davent on April 08, 2015, 12:07:44 AM
Is it possible a power jack tab and output jack tab are making contact or a wire shorting in there abouts?

Don't they both need to go to ground?
Title: Re: Ground Issue?
Post by: davent on April 08, 2015, 12:32:48 AM
Hello,
If you mean both jacks, the in & out, each jack's ground tab needs to be connected to ground, assuming they are mono jacks, the other tab will be carrying signal, if it makes contact with ground no signal will be passed. I can't tell from the picture whether the signal/hot tab or wire is making contact with any grounded point around the power jack.

If it worked before boxing, my guess (and yours) is, in fitting it into the tiny 1590A  a signal short to ground was created, something that shouldn't be  touching the enclosure,(grounded) or some other grounded point is.
dave
Title: Re: Ground Issue?
Post by: jubal81 on April 08, 2015, 12:37:30 AM
Here's something I learned to look out for:


When you insert the cable plug, the jack connections move. This means that testing with no plug, everything looks OK. Plug it in and your guitar signal is going to ground.


I'd suggest plugging in your cables and using a DMM continuity setting, check to see if the tips or any other signal net is connected to ground.
Title: Re: Ground Issue?
Post by: alanp on April 08, 2015, 06:08:44 AM
You're a brave man, to have the power jack and signal jack THAT intimate!

Try swapping the internal-nut power jack for an external-nut type. It'll give you a few mil more clearance to play with.
Title: Re: Ground Issue?
Post by: luks999 on April 08, 2015, 09:07:34 AM
+1 on what the others said, i often had short circuits when pluggin in, and that was not nearly as tight to the power jack
can you make a foto with the jacks plugged in ?

plug the jacks in and measure for shorts without power. keep us updated