noob question on battery bypass

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noob question on battery bypass

Postby fetchzee » 10 May 2012, 16:14

Okay, first post, first build. I've put together a SHO (thanks guys), and the good news is that the effect works well and is quiet (i.e., signal and grounding appear to be good). My issue is that when the circuit is out of the enclosure (for testing purposes I'm using a cheap folded-metal Radio Shack enclosure box, Hammond box forthcoming), the input jack grounds out the power as it is supposed to. However, when I physically put the input and output jacks into their respective holes in the enclosure, the LED lights up when the pedal is engaged whether or not a cord is plugged into the input jack.

The wiring path I'm using is: negative lead from battery to negative terminal on DC jack to sleeve of input jack. Ring of input jack to footswitch to sleeve of output jack. Everything looks correct and the pedal is functioning fine, but I just cannot figure this out. The box is just plain folded aluminum - unpainted (I don't think bare-metal contact between the jacks and the enclosure would do anything, but I'm grasping at straws here). The input and output jacks are a couple of new parts-bin jacks I had lying around.

Where have I gone wrong?

Thanks all,

Z.
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Re: noob question on battery bypass

Postby PokeyPete » 10 May 2012, 17:27

Your wiring is off a little bit. Check it against this illustration from Madbean's site:

http://www.madbeanpedals.com/tutorials/ ... ng_MBP.pdf
“No man is so foolish but he may sometimes give another
good counsel, and no man so wise that he may not easily err
if he takes no other counsel than his own. He that is taught
only by himself has a fool for a master.”
–Hunter S. Thompson
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Re: noob question on battery bypass

Postby fetchzee » 10 May 2012, 17:44

PokeyPete wrote:Your wiring is off a little bit. Check it against this illustration from Madbean's site:

http://www.madbeanpedals.com/tutorials/ ... ng_MBP.pdf


Okay, thanks . . . I was using the Beavis Audio diagram:

http://beavisaudio.com/techpages/SchematicToReality/fig8.1.gif

I'll try the Madbean diagram and see if it makes a difference.

Thanks again!
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Re: noob question on battery bypass

Postby PokeyPete » 10 May 2012, 19:18

fetchzee wrote:
PokeyPete wrote:Your wiring is off a little bit. Check it against this illustration from Madbean's site:

http://www.madbeanpedals.com/tutorials/ ... ng_MBP.pdf


Okay, thanks . . . I was using the Beavis Audio diagram:

http://beavisaudio.com/techpages/SchematicToReality/fig8.1.gif

I'll try the Madbean diagram and see if it makes a difference.

Thanks again!

I took a look at the drawing on the site you were using. Their intention was to employ the same input power switching scheme,
but where they messed up is that connection from input ring to switch to output sleeve. They should have omitted the wire
from the switch to output sleeve. The case connects the sleeves of both jacks to ground. By running that wire from the output
jack's sleeve (ground) to the switch, they bypassed the necessity of having to plug into the input jack in order to complete the
ground connection. If you simply cut that wire out, your wiring will probably work fine.
“No man is so foolish but he may sometimes give another
good counsel, and no man so wise that he may not easily err
if he takes no other counsel than his own. He that is taught
only by himself has a fool for a master.”
–Hunter S. Thompson
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Posts: 372
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