madbeanpedals::forum

General => Open Discussion => Topic started by: sdlogan9 on January 04, 2015, 02:16:38 PM

Title: Advice with 9v battery supply wiring!
Post by: sdlogan9 on January 04, 2015, 02:16:38 PM
Some customers, but not all have reported difficulty with grounding issues when using the battery only.


What is the preferred / best way to wire the ground in this situation?

Wire Ground of the battery snap to the ground of the  9v DC Power Jack?

or

Wire Ground to the Sleeve of the Input or Output Jack?


(http://i10.photobucket.com/albums/a103/sdlogan9/KLONE/photo5_zps835226c4.jpg) (http://s10.photobucket.com/user/sdlogan9/media/KLONE/photo5_zps835226c4.jpg.html)


Some customers not all but some have reported difficulty with grounding issues when using the battery only.
Title: Re: Advice with 9v battery supply wiring!
Post by: TGP39 on January 04, 2015, 02:56:11 PM
I always wire my 9volt battery grounding wire to the ring of the input jack. Hope this helps....
Title: Re: Advice with 9v battery supply wiring!
Post by: hubb on January 04, 2015, 03:15:37 PM
Heres's a build doc from madbean that has a typical wiring diagram.
http://www.madbeanpedals.com/projects/Mudbunny/docs/Mudbunny2014.pdf


I *think* that by grounding to the sleeve of the input jack the enclosure then becomes grounded.

It looks like the inside of the enclosure is painted, is it possible that the jacks aren't making good contact with the enclosure?  You may want to try sanding down the inside of the enclosure where the jacks make contact to ensure that the ground can be carried by the enclosure if nothing else works.
Title: Re: Advice with 9v battery supply wiring!
Post by: TGP39 on January 04, 2015, 04:31:50 PM
Am I missing something here? What is keeping this 9 volt from draining when not in use?  You need a TRS stereo input jack so that the circuit is open when the stereo cable is unplugged from the input jack.  If I'm misunderstanding your wiring scheme I apologize.
Title: Re: Advice with 9v battery supply wiring!
Post by: davent on January 04, 2015, 05:08:13 PM
 Add star-inner-toothed lock washers between the input/output jack to ensure excellent contact betweeen the enclosure and the jacks and help keep them tight. Like mentioned sand away any paint on the inside of the enclosure under the jacks.
Title: Re: Advice with 9v battery supply wiring!
Post by: mremic01 on January 04, 2015, 06:42:54 PM
Quote from: davent on January 04, 2015, 05:08:13 PM
Add star-inner-toothed lock washers between the input/output jack to ensure excellent contact betweeen the enclosure and the jacks and help keep them tight. Like mentioned sand away any paint on the inside of the enclosure under the jacks.

All the paint on the inside of the enclosure looks like this could be a help. I've never had a problem with a jack making solid contact with the enclosure (there's so much surface area for it touch that it just always has a good connection), but I don't paint on the inside.

A more glaring issue is the use of mono jacks. Conventionally, one of the jacks should be stereo. The mono instrument cable's plug then acts as an on/off switch for the battery, connecting the ring and the sleeve. The neg lead of the battery snap then gets disconnected from ground when you unplug the cable. If you don't do this, the effect will powered on ALL THE TIME unless the customer physically removes the battery. This kills the battery.

But connecting the neg lead of the snap to either the ground lug on the DC jack or either sleeve will work. If the grounding issue is only happening with the battery and not with a wall wart, then it might not actually be a grounding issue.